diff --git "a/CMU Advanced NLP 2024 (1) Introduction to NLP/transcript.vtt" "b/CMU Advanced NLP 2024 (1) Introduction to NLP/transcript.vtt" new file mode 100644--- /dev/null +++ "b/CMU Advanced NLP 2024 (1) Introduction to NLP/transcript.vtt" @@ -0,0 +1,4555 @@ +WEBVTT + +00:00:01.280 --> 00:00:06.759 +so the class today is uh introduction to + +00:00:04.680 --> 00:00:09.480 +natural language processing and I'll be + +00:00:06.759 --> 00:00:11.200 +talking a little bit about you know what + +00:00:09.480 --> 00:00:14.719 +is natural language processing why we're + +00:00:11.200 --> 00:00:16.720 +motivated to do it and also some of the + +00:00:14.719 --> 00:00:18.039 +difficulties that we encounter and I'll + +00:00:16.720 --> 00:00:19.880 +at the end I'll also be talking about + +00:00:18.039 --> 00:00:22.519 +class Logistics so you can ask any + +00:00:19.880 --> 00:00:25.439 +Logistics questions at that + +00:00:22.519 --> 00:00:27.720 +time so if we talk about what is NLP + +00:00:25.439 --> 00:00:29.320 +anyway uh does anyone have any opinions + +00:00:27.720 --> 00:00:31.439 +about the definition of what natural + +00:00:29.320 --> 00:00:33.239 +language process would be oh one other + +00:00:31.439 --> 00:00:35.680 +thing I should mention is I am recording + +00:00:33.239 --> 00:00:38.600 +the class uh I put the class on YouTube + +00:00:35.680 --> 00:00:40.520 +uh afterwards I will not take pictures + +00:00:38.600 --> 00:00:41.920 +or video of any of you uh but if you + +00:00:40.520 --> 00:00:44.719 +talk your voice might come in the + +00:00:41.920 --> 00:00:47.440 +background so just uh be aware of that + +00:00:44.719 --> 00:00:49.000 +um usually not it's a directional mic so + +00:00:47.440 --> 00:00:51.559 +I try to repeat the questions after + +00:00:49.000 --> 00:00:54.079 +everybody um but uh for the people who + +00:00:51.559 --> 00:00:57.680 +are recordings uh listening to the + +00:00:54.079 --> 00:00:59.320 +recordings um so anyway what is NLP + +00:00:57.680 --> 00:01:03.120 +anyway does anybody have any ideas about + +00:00:59.320 --> 00:01:03.120 +the definition of what NLP might + +00:01:06.119 --> 00:01:09.119 +be + +00:01:15.439 --> 00:01:21.759 +yes okay um it so the answer was it + +00:01:19.240 --> 00:01:25.759 +helps machines understand language + +00:01:21.759 --> 00:01:27.920 +better uh so to facilitate human human + +00:01:25.759 --> 00:01:31.159 +and human machine interactions I think + +00:01:27.920 --> 00:01:32.759 +that's very good um it's + +00:01:31.159 --> 00:01:36.520 +uh similar to what I have written on my + +00:01:32.759 --> 00:01:38.040 +slide here uh but natur in addition to + +00:01:36.520 --> 00:01:41.280 +natural language understanding there's + +00:01:38.040 --> 00:01:46.000 +one major other segment of NLP uh does + +00:01:41.280 --> 00:01:46.000 +anyone uh have an idea what that might + +00:01:48.719 --> 00:01:53.079 +be we often have a dichotomy between two + +00:01:51.399 --> 00:01:55.240 +major segments natural language + +00:01:53.079 --> 00:01:57.520 +understanding and natural language + +00:01:55.240 --> 00:01:59.439 +generation yeah exactly so I I would say + +00:01:57.520 --> 00:02:03.119 +that's almost perfect if you had said + +00:01:59.439 --> 00:02:06.640 +understand and generate so very good um + +00:02:03.119 --> 00:02:08.560 +so I I say natural technology to handle + +00:02:06.640 --> 00:02:11.400 +human language usually text using + +00:02:08.560 --> 00:02:13.200 +computers uh to Aid human machine + +00:02:11.400 --> 00:02:15.480 +communication and this can include + +00:02:13.200 --> 00:02:17.879 +things like question answering dialogue + +00:02:15.480 --> 00:02:20.840 +or generation of code that can be + +00:02:17.879 --> 00:02:23.239 +executed with uh + +00:02:20.840 --> 00:02:25.080 +computers it can also Aid human human + +00:02:23.239 --> 00:02:27.440 +communication and this can include + +00:02:25.080 --> 00:02:30.440 +things like machine translation or spell + +00:02:27.440 --> 00:02:32.640 +checking or assisted writing + +00:02:30.440 --> 00:02:34.560 +and then a final uh segment that people + +00:02:32.640 --> 00:02:37.400 +might think about a little bit less is + +00:02:34.560 --> 00:02:39.400 +analyzing and understanding a language + +00:02:37.400 --> 00:02:42.400 +and this includes things like syntactic + +00:02:39.400 --> 00:02:44.959 +analysis text classification entity + +00:02:42.400 --> 00:02:47.400 +recognition and linking and these can be + +00:02:44.959 --> 00:02:49.159 +used for uh various reasons not + +00:02:47.400 --> 00:02:51.000 +necessarily for direct human machine + +00:02:49.159 --> 00:02:52.720 +communication but also for like + +00:02:51.000 --> 00:02:54.400 +aggregating information across large + +00:02:52.720 --> 00:02:55.760 +things for scientific studies and other + +00:02:54.400 --> 00:02:57.519 +things like that I'll give a few + +00:02:55.760 --> 00:03:00.920 +examples of + +00:02:57.519 --> 00:03:04.040 +this um we now use an many times a day + +00:03:00.920 --> 00:03:06.480 +sometimes without even knowing it so uh + +00:03:04.040 --> 00:03:09.400 +whenever you're typing a doc in Google + +00:03:06.480 --> 00:03:11.599 +Docs there's you know spell checking and + +00:03:09.400 --> 00:03:13.959 +grammar checking going on behind it's + +00:03:11.599 --> 00:03:15.920 +gotten frighten frighteningly good + +00:03:13.959 --> 00:03:18.280 +recently that where it checks like most + +00:03:15.920 --> 00:03:20.720 +of my mistakes and rarely Flags things + +00:03:18.280 --> 00:03:22.799 +that are not mistakes so obviously they + +00:03:20.720 --> 00:03:25.080 +have powerful models running behind that + +00:03:22.799 --> 00:03:25.080 +uh + +00:03:25.640 --> 00:03:33.080 +so and it can do things like answer + +00:03:28.720 --> 00:03:34.599 +questions uh so I asked chat GPT who is + +00:03:33.080 --> 00:03:37.000 +the current president of Carnegie melan + +00:03:34.599 --> 00:03:38.920 +University and chat GPT said I did a + +00:03:37.000 --> 00:03:40.920 +quick search for more information here + +00:03:38.920 --> 00:03:43.439 +is what I found uh the current president + +00:03:40.920 --> 00:03:47.120 +of car Mel University is faram Janan he + +00:03:43.439 --> 00:03:50.040 +has been serving since July 1 etc etc so + +00:03:47.120 --> 00:03:50.040 +as far as I can tell that's + +00:03:50.400 --> 00:03:56.319 +correct um at the same time I asked how + +00:03:53.799 --> 00:04:00.280 +many layers are included in the GP 3.5 + +00:03:56.319 --> 00:04:02.360 +turbo architecture and it said to me + +00:04:00.280 --> 00:04:05.400 +GPT 3.5 turbo which is an optimized + +00:04:02.360 --> 00:04:07.239 +version of GPT 3.5 for faster responses + +00:04:05.400 --> 00:04:08.959 +doesn't have a specific layer art + +00:04:07.239 --> 00:04:11.720 +structure like the traditional gpt3 + +00:04:08.959 --> 00:04:13.560 +models um and I don't know if this is + +00:04:11.720 --> 00:04:16.600 +true or not but I'm pretty sure it's not + +00:04:13.560 --> 00:04:18.840 +true I'm pretty sure that you know GPT + +00:04:16.600 --> 00:04:20.560 +is a model that's much like other models + +00:04:18.840 --> 00:04:21.560 +uh so it basically just made up the spec + +00:04:20.560 --> 00:04:22.880 +because it didn't have any information + +00:04:21.560 --> 00:04:26.000 +on the Internet or couldn't talk about + +00:04:22.880 --> 00:04:26.000 +it so + +00:04:26.120 --> 00:04:33.479 +um another thing is uh NLP can translate + +00:04:29.639 --> 00:04:37.759 +text pretty well so I ran um Google + +00:04:33.479 --> 00:04:39.560 +translate uh on Japanese uh this example + +00:04:37.759 --> 00:04:41.639 +is a little bit old it's from uh you + +00:04:39.560 --> 00:04:44.639 +know a few years ago about Co but I I + +00:04:41.639 --> 00:04:46.240 +retranslated it a few days ago and it + +00:04:44.639 --> 00:04:47.680 +comes up pretty good uh you can + +00:04:46.240 --> 00:04:49.639 +basically understand what's going on + +00:04:47.680 --> 00:04:53.520 +here it's not perfect but you can + +00:04:49.639 --> 00:04:56.400 +understand the uh the general uh + +00:04:53.520 --> 00:04:58.560 +gist at the same time uh if I put in a + +00:04:56.400 --> 00:05:02.280 +relatively low resource language this is + +00:04:58.560 --> 00:05:05.759 +Kurdish um it has a number of problems + +00:05:02.280 --> 00:05:08.199 +when you try to understand it and just + +00:05:05.759 --> 00:05:12.400 +to give an example this is talking about + +00:05:08.199 --> 00:05:14.320 +uh some uh paleontology Discovery it + +00:05:12.400 --> 00:05:15.800 +called this person a fossil scientist + +00:05:14.320 --> 00:05:17.440 +instead of the kind of obvious English + +00:05:15.800 --> 00:05:20.120 +term + +00:05:17.440 --> 00:05:23.520 +paleontologist um and it's talking about + +00:05:20.120 --> 00:05:25.240 +three different uh T-Rex species uh how + +00:05:23.520 --> 00:05:27.039 +T-Rex should actually be split into + +00:05:25.240 --> 00:05:29.639 +three species where T-Rex says king of + +00:05:27.039 --> 00:05:31.560 +ferocious lizards emperator says emperor + +00:05:29.639 --> 00:05:33.720 +of Savaged lizards and then T Regina + +00:05:31.560 --> 00:05:35.120 +means clean of ferocious snail I'm + +00:05:33.720 --> 00:05:37.240 +pretty sure that's not snail I'm pretty + +00:05:35.120 --> 00:05:41.080 +sure that's lizard so uh you can see + +00:05:37.240 --> 00:05:41.080 +that this is not uh this is not perfect + +00:05:41.280 --> 00:05:46.680 +either some people might be thinking why + +00:05:43.960 --> 00:05:48.400 +Google translate and why not GPD well it + +00:05:46.680 --> 00:05:49.960 +turns out um according to one of the + +00:05:48.400 --> 00:05:51.759 +recent studies we've done GPD is even + +00:05:49.960 --> 00:05:55.479 +worse at these slow resource languages + +00:05:51.759 --> 00:05:58.120 +so I use the best thing that's out + +00:05:55.479 --> 00:06:00.440 +there um another thing is language + +00:05:58.120 --> 00:06:02.039 +analysis can Aid scientific ific inquiry + +00:06:00.440 --> 00:06:03.600 +so this is an example that I've been + +00:06:02.039 --> 00:06:06.120 +using for a long time it's actually from + +00:06:03.600 --> 00:06:09.160 +Martin sap another faculty member here + +00:06:06.120 --> 00:06:12.440 +uh but I have been using it since uh + +00:06:09.160 --> 00:06:14.160 +like before he joined and it uh this is + +00:06:12.440 --> 00:06:16.039 +an example from computational social + +00:06:14.160 --> 00:06:18.599 +science uh answering questions about + +00:06:16.039 --> 00:06:20.240 +Society given observational data and + +00:06:18.599 --> 00:06:22.280 +their question was do movie scripts + +00:06:20.240 --> 00:06:24.599 +portray female or male characters with + +00:06:22.280 --> 00:06:27.520 +more power or agency in movie script + +00:06:24.599 --> 00:06:30.120 +films so it's asking kind of a so + +00:06:27.520 --> 00:06:32.160 +societal question by using NLP + +00:06:30.120 --> 00:06:35.360 +technology and the way they did it is + +00:06:32.160 --> 00:06:36.880 +they basically analyzed text trying to + +00:06:35.360 --> 00:06:43.080 +find + +00:06:36.880 --> 00:06:45.280 +uh the uh agents and patients in a a + +00:06:43.080 --> 00:06:46.479 +particular text which are the the things + +00:06:45.280 --> 00:06:49.280 +that are doing things and the things + +00:06:46.479 --> 00:06:52.639 +that things are being done to and you + +00:06:49.280 --> 00:06:54.440 +can see that essentially male characters + +00:06:52.639 --> 00:06:56.560 +in these movie scripts were given more + +00:06:54.440 --> 00:06:58.080 +power in agency and female characters + +00:06:56.560 --> 00:06:59.960 +were given less power in agency and they + +00:06:58.080 --> 00:07:02.680 +were able to do this because they had + +00:06:59.960 --> 00:07:04.840 +NLP technology that analyzed and + +00:07:02.680 --> 00:07:08.960 +extracted useful data and made turned it + +00:07:04.840 --> 00:07:11.520 +into a very easy form to do kind of + +00:07:08.960 --> 00:07:15.840 +analysis of the variety that they want + +00:07:11.520 --> 00:07:17.400 +so um I think that's a major use case of + +00:07:15.840 --> 00:07:19.400 +NLP technology that does language + +00:07:17.400 --> 00:07:20.919 +analysis nowadays turn it into a form + +00:07:19.400 --> 00:07:23.960 +that allows you to very quickly do + +00:07:20.919 --> 00:07:27.440 +aggregate queries and other things like + +00:07:23.960 --> 00:07:30.479 +this um but at the same time uh language + +00:07:27.440 --> 00:07:33.520 +analysis tools fail at very basic tasks + +00:07:30.479 --> 00:07:36.000 +so these are + +00:07:33.520 --> 00:07:38.199 +some things that I ran through a named + +00:07:36.000 --> 00:07:41.080 +entity recognizer and these were kind of + +00:07:38.199 --> 00:07:43.160 +very nice named entity recognizers uh + +00:07:41.080 --> 00:07:46.240 +that a lot of people were using for + +00:07:43.160 --> 00:07:48.039 +example Stanford core NLP and Spacey and + +00:07:46.240 --> 00:07:50.319 +both of them I just threw in the first + +00:07:48.039 --> 00:07:53.120 +thing that I found on the New York Times + +00:07:50.319 --> 00:07:55.199 +at the time and it basically made at + +00:07:53.120 --> 00:07:58.319 +least one mistake in the first sentence + +00:07:55.199 --> 00:08:00.840 +and here it recognizes Baton Rouge as an + +00:07:58.319 --> 00:08:04.720 +organization and here it recognized + +00:08:00.840 --> 00:08:07.000 +hurricane EA as an organization so um + +00:08:04.720 --> 00:08:08.879 +like even uh these things that we expect + +00:08:07.000 --> 00:08:10.360 +should work pretty well make pretty + +00:08:08.879 --> 00:08:13.360 +Solly + +00:08:10.360 --> 00:08:16.199 +mistakes so in the class uh basically + +00:08:13.360 --> 00:08:18.479 +what I want to cover is uh what goes + +00:08:16.199 --> 00:08:20.360 +into building uh state-of-the-art NLP + +00:08:18.479 --> 00:08:24.000 +systems that work really well on a wide + +00:08:20.360 --> 00:08:26.240 +variety of tasks um where do current + +00:08:24.000 --> 00:08:28.840 +systems + +00:08:26.240 --> 00:08:30.479 +fail and how can we make appropriate + +00:08:28.840 --> 00:08:35.000 +improvements and Achieve whatever we + +00:08:30.479 --> 00:08:37.719 +want to do with nalp and this set of + +00:08:35.000 --> 00:08:39.360 +questions that I'm asking here is + +00:08:37.719 --> 00:08:40.919 +exactly the same as the set of questions + +00:08:39.360 --> 00:08:43.519 +that I was asking two years ago before + +00:08:40.919 --> 00:08:45.480 +chat GPT uh I still think they're + +00:08:43.519 --> 00:08:46.920 +important questions but I think the + +00:08:45.480 --> 00:08:48.399 +answers to these questions is very + +00:08:46.920 --> 00:08:50.040 +different and because of that we're + +00:08:48.399 --> 00:08:52.120 +updating the class materials to try to + +00:08:50.040 --> 00:08:54.399 +cover you know the answers to these + +00:08:52.120 --> 00:08:56.000 +questions and uh in kind of the era of + +00:08:54.399 --> 00:08:58.200 +large language models and other things + +00:08:56.000 --> 00:08:59.720 +like + +00:08:58.200 --> 00:09:02.079 +that + +00:08:59.720 --> 00:09:03.360 +so that's all I have for the intro maybe + +00:09:02.079 --> 00:09:06.640 +maybe pretty straightforward are there + +00:09:03.360 --> 00:09:08.480 +any questions or comments so far if not + +00:09:06.640 --> 00:09:14.399 +I'll I'll just go + +00:09:08.480 --> 00:09:17.160 +on okay great so I want to uh first go + +00:09:14.399 --> 00:09:19.480 +into a very high Lev overview of NLP + +00:09:17.160 --> 00:09:20.839 +system building and most of the stuff + +00:09:19.480 --> 00:09:22.399 +that I want to do today is to set the + +00:09:20.839 --> 00:09:24.320 +stage for what I'm going to be talking + +00:09:22.399 --> 00:09:25.040 +about in more detail uh over the rest of + +00:09:24.320 --> 00:09:29.200 +the + +00:09:25.040 --> 00:09:31.720 +class and we could think of NLP syst + +00:09:29.200 --> 00:09:34.040 +systems through this kind of General + +00:09:31.720 --> 00:09:36.560 +framework where we want to create a + +00:09:34.040 --> 00:09:40.600 +function to map an input X into an + +00:09:36.560 --> 00:09:44.440 +output y uh where X and or Y involve + +00:09:40.600 --> 00:09:47.000 +language and uh do some people have + +00:09:44.440 --> 00:09:50.120 +favorite NLP tasks or NLP tasks that you + +00:09:47.000 --> 00:09:52.399 +want to uh want to be handling in some + +00:09:50.120 --> 00:09:57.000 +way or maybe what what do you think are + +00:09:52.399 --> 00:09:57.000 +the most popular and important NLP tasks + +00:09:58.120 --> 00:10:03.200 +nowadays + +00:10:00.800 --> 00:10:06.120 +okay so translation is maybe easy what's + +00:10:03.200 --> 00:10:06.120 +the input and output of + +00:10:11.440 --> 00:10:15.720 +translation okay yeah so uh in + +00:10:13.800 --> 00:10:17.959 +Translation inputs text in one language + +00:10:15.720 --> 00:10:21.760 +output is text in another language and + +00:10:17.959 --> 00:10:21.760 +then what what is a good + +00:10:27.680 --> 00:10:32.160 +translation yeah corre or or the same is + +00:10:30.320 --> 00:10:35.839 +the input basically yes um it also + +00:10:32.160 --> 00:10:37.760 +should be fluent but I agree any other + +00:10:35.839 --> 00:10:39.839 +things generation the reason why I said + +00:10:37.760 --> 00:10:41.519 +it's tough is it's pretty broad um and + +00:10:39.839 --> 00:10:43.360 +it's not like we could be doing + +00:10:41.519 --> 00:10:46.360 +generation with lots of different inputs + +00:10:43.360 --> 00:10:51.440 +but um yeah any any other things maybe a + +00:10:46.360 --> 00:10:51.440 +little bit different yeah like + +00:10:51.480 --> 00:10:55.959 +scenario a scenario and a multiple + +00:10:54.000 --> 00:10:58.200 +choice question about the scenario and + +00:10:55.959 --> 00:10:59.680 +so what would the scenario in the + +00:10:58.200 --> 00:11:01.760 +multiple choice question are probably + +00:10:59.680 --> 00:11:04.040 +the input and then the output + +00:11:01.760 --> 00:11:06.480 +is an answer to the multiple choice + +00:11:04.040 --> 00:11:07.920 +question um and then there it's kind of + +00:11:06.480 --> 00:11:12.279 +obvious like what is good it's the + +00:11:07.920 --> 00:11:14.880 +correct answer sure um interestingly I + +00:11:12.279 --> 00:11:17.440 +think a lot of llm evaluation is done on + +00:11:14.880 --> 00:11:21.160 +these multiple choice questions but I'm + +00:11:17.440 --> 00:11:22.320 +yet to encounter an actual application + +00:11:21.160 --> 00:11:24.880 +that cares about multiple choice + +00:11:22.320 --> 00:11:26.880 +question answering so uh there's kind of + +00:11:24.880 --> 00:11:30.959 +a funny disconnect there but uh yeah I + +00:11:26.880 --> 00:11:33.519 +saw hand that think about V search comp + +00:11:30.959 --> 00:11:36.360 +yeah Vector search uh that's very good + +00:11:33.519 --> 00:11:36.360 +so the input + +00:11:37.120 --> 00:11:45.000 +is can con it into or understanding and + +00:11:42.560 --> 00:11:45.000 +it to + +00:11:47.360 --> 00:11:53.760 +another okay yeah so I'd say the input + +00:11:49.880 --> 00:11:56.160 +there is a query and a document base um + +00:11:53.760 --> 00:11:57.959 +and then the output is maybe an index + +00:11:56.160 --> 00:11:59.800 +into the document or or something else + +00:11:57.959 --> 00:12:01.279 +like that sure um and then something + +00:11:59.800 --> 00:12:05.040 +that's good here here's a good question + +00:12:01.279 --> 00:12:05.040 +what what's a good result from + +00:12:06.560 --> 00:12:10.200 +that what's a good + +00:12:10.839 --> 00:12:19.279 +output be sort of simar the major + +00:12:15.560 --> 00:12:21.680 +problem there I see is how you def SAR + +00:12:19.279 --> 00:12:26.199 +and how you + +00:12:21.680 --> 00:12:29.760 +a always like you understand + +00:12:26.199 --> 00:12:33.000 +whether is actually + +00:12:29.760 --> 00:12:35.079 +yeah exactly so that um just to repeat + +00:12:33.000 --> 00:12:36.880 +it's like uh we need to have a + +00:12:35.079 --> 00:12:38.399 +similarity a good similarity metric we + +00:12:36.880 --> 00:12:40.120 +need to have a good threshold where we + +00:12:38.399 --> 00:12:41.760 +get like the ones we want and we don't + +00:12:40.120 --> 00:12:43.240 +get the ones we don't want we're going + +00:12:41.760 --> 00:12:44.959 +to talk more about that in the retrieval + +00:12:43.240 --> 00:12:48.440 +lecture exactly how we evaluate and + +00:12:44.959 --> 00:12:49.920 +stuff but um yeah good so this is a good + +00:12:48.440 --> 00:12:53.279 +uh here are some good examples I have + +00:12:49.920 --> 00:12:55.519 +some examples of my own um the first one + +00:12:53.279 --> 00:12:58.360 +is uh kind of the very generic one maybe + +00:12:55.519 --> 00:13:00.800 +kind of like generation here but text in + +00:12:58.360 --> 00:13:02.959 +continuing text uh so this is language + +00:13:00.800 --> 00:13:04.160 +modeling so you have a text and then you + +00:13:02.959 --> 00:13:05.440 +have the continuation you want to + +00:13:04.160 --> 00:13:07.680 +predict the + +00:13:05.440 --> 00:13:10.480 +continuation um text and text in another + +00:13:07.680 --> 00:13:13.040 +language is translation uh text in a + +00:13:10.480 --> 00:13:15.800 +label could be text classification uh + +00:13:13.040 --> 00:13:17.760 +text in linguistic structure or uh some + +00:13:15.800 --> 00:13:21.360 +s kind of entities or something like + +00:13:17.760 --> 00:13:22.680 +that could be uh language analysis or um + +00:13:21.360 --> 00:13:24.839 +information + +00:13:22.680 --> 00:13:29.440 +extraction uh we could also have image + +00:13:24.839 --> 00:13:31.320 +and text uh which is image captioning um + +00:13:29.440 --> 00:13:33.560 +or speech and text which is speech + +00:13:31.320 --> 00:13:35.240 +recognition and I take the very broad + +00:13:33.560 --> 00:13:38.000 +view of natural language processing + +00:13:35.240 --> 00:13:39.519 +which is if it's any variety of language + +00:13:38.000 --> 00:13:41.519 +uh if you're handling language in some + +00:13:39.519 --> 00:13:42.800 +way it's natural language processing it + +00:13:41.519 --> 00:13:45.880 +doesn't necessarily have to be text + +00:13:42.800 --> 00:13:47.480 +input text output um so that's relevant + +00:13:45.880 --> 00:13:50.199 +for the projects that you're thinking + +00:13:47.480 --> 00:13:52.160 +about too at the end of this course so + +00:13:50.199 --> 00:13:55.519 +the the most common FAQ for this course + +00:13:52.160 --> 00:13:57.839 +is does my project count and if you're + +00:13:55.519 --> 00:13:59.360 +uncertain you should ask but usually + +00:13:57.839 --> 00:14:01.040 +like if it has some sort of language + +00:13:59.360 --> 00:14:05.079 +involved then I'll usually say yes it + +00:14:01.040 --> 00:14:07.920 +does kind so um if it's like uh code to + +00:14:05.079 --> 00:14:09.680 +code there that's not code is not + +00:14:07.920 --> 00:14:11.480 +natural language it is language but it's + +00:14:09.680 --> 00:14:13.000 +not natural language so that might be + +00:14:11.480 --> 00:14:15.320 +borderline we might have to discuss + +00:14:13.000 --> 00:14:15.320 +about + +00:14:15.759 --> 00:14:21.800 +that cool um so next I'd like to talk + +00:14:18.880 --> 00:14:25.240 +about methods for creating NLP systems + +00:14:21.800 --> 00:14:27.839 +um and there's a lot of different ways + +00:14:25.240 --> 00:14:29.720 +to create MLP systems all of these are + +00:14:27.839 --> 00:14:32.880 +alive and well in + +00:14:29.720 --> 00:14:35.759 +2024 uh the first one is Rule uh + +00:14:32.880 --> 00:14:37.959 +rule-based system creation and so the + +00:14:35.759 --> 00:14:40.399 +way this works is like let's say you + +00:14:37.959 --> 00:14:42.480 +want to build a text classifier you just + +00:14:40.399 --> 00:14:46.560 +write the simple python function that + +00:14:42.480 --> 00:14:48.639 +classifies things into uh sports or + +00:14:46.560 --> 00:14:50.240 +other and the way it classifies it into + +00:14:48.639 --> 00:14:52.959 +sports or other is it checks whether + +00:14:50.240 --> 00:14:55.160 +baseball soccer football and Tennis are + +00:14:52.959 --> 00:14:59.399 +included in the document and classifies + +00:14:55.160 --> 00:15:01.959 +it into uh Sports if so uh other if not + +00:14:59.399 --> 00:15:05.279 +so has anyone written something like + +00:15:01.959 --> 00:15:09.720 +this maybe not a text classifier but um + +00:15:05.279 --> 00:15:11.880 +you know to identify entities or uh + +00:15:09.720 --> 00:15:14.279 +split words + +00:15:11.880 --> 00:15:16.680 +or something like + +00:15:14.279 --> 00:15:18.399 +that has anybody not ever written + +00:15:16.680 --> 00:15:22.800 +anything like + +00:15:18.399 --> 00:15:24.639 +this yeah that's what I thought so um + +00:15:22.800 --> 00:15:26.079 +rule-based systems are very convenient + +00:15:24.639 --> 00:15:28.920 +when you don't really care about how + +00:15:26.079 --> 00:15:30.759 +good your system is um or you're doing + +00:15:28.920 --> 00:15:32.360 +that's really really simple and like + +00:15:30.759 --> 00:15:35.600 +it'll be perfect even if you do the very + +00:15:32.360 --> 00:15:37.079 +simple thing and so I I think it's worth + +00:15:35.600 --> 00:15:39.959 +talking a little bit about them and I'll + +00:15:37.079 --> 00:15:43.319 +talk a little bit about that uh this + +00:15:39.959 --> 00:15:45.680 +time the second thing which like very + +00:15:43.319 --> 00:15:47.680 +rapidly over the course of maybe three + +00:15:45.680 --> 00:15:50.279 +years or so has become actually maybe + +00:15:47.680 --> 00:15:52.720 +the dominant Paradigm in NLP is + +00:15:50.279 --> 00:15:56.360 +prompting uh in prompting a language + +00:15:52.720 --> 00:15:58.560 +model and the way this works is uh you + +00:15:56.360 --> 00:16:00.720 +ask a language model if the following + +00:15:58.560 --> 00:16:03.079 +sent is about sports reply Sports + +00:16:00.720 --> 00:16:06.120 +otherwise reply other and you feed it to + +00:16:03.079 --> 00:16:08.480 +your favorite LM uh usually that's GPT + +00:16:06.120 --> 00:16:11.399 +something or other uh sometimes it's an + +00:16:08.480 --> 00:16:14.440 +open source model of some variety and + +00:16:11.399 --> 00:16:17.759 +then uh it will give you the + +00:16:14.440 --> 00:16:20.639 +answer and then finally uh fine-tuning + +00:16:17.759 --> 00:16:22.240 +uh so you take some paired data and you + +00:16:20.639 --> 00:16:23.600 +do machine learning from paired data + +00:16:22.240 --> 00:16:25.680 +where you have something like I love to + +00:16:23.600 --> 00:16:27.440 +play baseball uh the stock price is + +00:16:25.680 --> 00:16:29.519 +going up he got a hatrick yesterday he + +00:16:27.440 --> 00:16:32.759 +is wearing tennis shoes and you assign + +00:16:29.519 --> 00:16:35.319 +all these uh labels to them training a + +00:16:32.759 --> 00:16:38.160 +model and you can even start out with a + +00:16:35.319 --> 00:16:41.480 +prompting based model and fine-tune a a + +00:16:38.160 --> 00:16:41.480 +language model + +00:16:42.920 --> 00:16:49.399 +also so one major consideration when + +00:16:47.519 --> 00:16:52.000 +you're Building Systems like this is the + +00:16:49.399 --> 00:16:56.440 +data requirements for building such a + +00:16:52.000 --> 00:16:59.319 +system and for rules or prompting where + +00:16:56.440 --> 00:17:02.240 +it's just based on intuition really no + +00:16:59.319 --> 00:17:04.640 +data is needed whatsoever it you don't + +00:17:02.240 --> 00:17:08.240 +need a single example and you can start + +00:17:04.640 --> 00:17:11.000 +writing rules or like just just to give + +00:17:08.240 --> 00:17:12.640 +an example the rules and prompts I wrote + +00:17:11.000 --> 00:17:14.679 +here I didn't look at any examples and I + +00:17:12.640 --> 00:17:17.240 +just wrote them uh so this is something + +00:17:14.679 --> 00:17:20.000 +that you could start out + +00:17:17.240 --> 00:17:21.559 +with uh the problem is you also have no + +00:17:20.000 --> 00:17:24.720 +idea how well it works if you don't have + +00:17:21.559 --> 00:17:26.760 +any data whatsoever right so um you'll + +00:17:24.720 --> 00:17:30.400 +you might be in trouble if you think + +00:17:26.760 --> 00:17:30.400 +something should be working + +00:17:30.919 --> 00:17:34.440 +so normally the next thing that people + +00:17:32.919 --> 00:17:36.880 +move to nowadays when they're building + +00:17:34.440 --> 00:17:39.559 +practical systems is rules are prompting + +00:17:36.880 --> 00:17:41.240 +based on spot checks so that basically + +00:17:39.559 --> 00:17:42.919 +means that you start out with a + +00:17:41.240 --> 00:17:45.840 +rule-based system or a prompting based + +00:17:42.919 --> 00:17:47.240 +system and then you go in and you run it + +00:17:45.840 --> 00:17:48.720 +on some data that you're interested in + +00:17:47.240 --> 00:17:50.799 +you just kind of qualitatively look at + +00:17:48.720 --> 00:17:52.160 +the data and say oh it's messing up here + +00:17:50.799 --> 00:17:53.440 +then you go in and fix your prompt a + +00:17:52.160 --> 00:17:54.919 +little bit or you go in and fix your + +00:17:53.440 --> 00:17:57.320 +rules a little bit or something like + +00:17:54.919 --> 00:18:00.400 +that so uh this is kind of the second + +00:17:57.320 --> 00:18:00.400 +level of difficulty + +00:18:01.400 --> 00:18:04.640 +so the third level of difficulty would + +00:18:03.159 --> 00:18:07.400 +be something like rules are prompting + +00:18:04.640 --> 00:18:09.039 +with rigorous evaluation and so here you + +00:18:07.400 --> 00:18:12.840 +would create a development set with + +00:18:09.039 --> 00:18:14.840 +inputs and outputs uh so you uh create + +00:18:12.840 --> 00:18:17.039 +maybe 200 to 2,000 + +00:18:14.840 --> 00:18:20.080 +examples um + +00:18:17.039 --> 00:18:21.720 +and then evaluate your actual accuracy + +00:18:20.080 --> 00:18:23.880 +so you need an evaluation metric you + +00:18:21.720 --> 00:18:26.120 +need other things like this this is the + +00:18:23.880 --> 00:18:28.400 +next level of difficulty but if you're + +00:18:26.120 --> 00:18:30.240 +going to be a serious you know NLP + +00:18:28.400 --> 00:18:33.000 +engineer or something like this you + +00:18:30.240 --> 00:18:34.720 +definitely will be doing this a lot I + +00:18:33.000 --> 00:18:37.760 +feel and + +00:18:34.720 --> 00:18:40.360 +then so that here now you start needing + +00:18:37.760 --> 00:18:41.960 +a depth set and a test set and then + +00:18:40.360 --> 00:18:46.280 +finally fine-tuning you need an + +00:18:41.960 --> 00:18:48.480 +additional training set um and uh this + +00:18:46.280 --> 00:18:52.240 +will generally be a lot bigger than 200 + +00:18:48.480 --> 00:18:56.080 +to 2,000 examples and generally the rule + +00:18:52.240 --> 00:18:56.080 +is that every time you + +00:18:57.320 --> 00:19:01.080 +double + +00:18:59.520 --> 00:19:02.400 +every time you double your training set + +00:19:01.080 --> 00:19:07.480 +size you get about a constant + +00:19:02.400 --> 00:19:07.480 +Improvement so if you start + +00:19:07.799 --> 00:19:15.080 +out if you start out down here with + +00:19:12.240 --> 00:19:17.039 +um zero shot accuracy with a language + +00:19:15.080 --> 00:19:21.559 +model you you create a small printing + +00:19:17.039 --> 00:19:21.559 +set and you get you know a pretty big + +00:19:22.000 --> 00:19:29.120 +increase and then every time you double + +00:19:26.320 --> 00:19:30.799 +it it increases by constant fact it's + +00:19:29.120 --> 00:19:32.480 +kind of like just in general in machine + +00:19:30.799 --> 00:19:37.360 +learning this is a trend that we tend to + +00:19:32.480 --> 00:19:40.679 +see so um So based on this + +00:19:37.360 --> 00:19:41.880 +uh there's kind of like you get a big + +00:19:40.679 --> 00:19:44.200 +gain from having a little bit of + +00:19:41.880 --> 00:19:45.760 +training data but the gains very quickly + +00:19:44.200 --> 00:19:48.919 +drop off and you start spending a lot of + +00:19:45.760 --> 00:19:48.919 +time annotating + +00:19:51.000 --> 00:19:55.880 +an so um yeah this is the the general + +00:19:54.760 --> 00:19:58.280 +overview of the different types of + +00:19:55.880 --> 00:20:00.000 +system building uh any any question + +00:19:58.280 --> 00:20:01.559 +questions about this or comments or + +00:20:00.000 --> 00:20:04.000 +things like + +00:20:01.559 --> 00:20:05.840 +this I think one thing that's changed + +00:20:04.000 --> 00:20:08.159 +really drastically from the last time I + +00:20:05.840 --> 00:20:09.600 +taught this class is the fact that + +00:20:08.159 --> 00:20:11.000 +number one and number two are the things + +00:20:09.600 --> 00:20:13.799 +that people are actually doing in + +00:20:11.000 --> 00:20:15.360 +practice uh which was you know people + +00:20:13.799 --> 00:20:16.679 +who actually care about systems are + +00:20:15.360 --> 00:20:18.880 +doing number one and number two is the + +00:20:16.679 --> 00:20:20.440 +main thing it used to be that if you + +00:20:18.880 --> 00:20:22.679 +were actually serious about building a + +00:20:20.440 --> 00:20:24.320 +system uh you really needed to do the + +00:20:22.679 --> 00:20:27.080 +funing and now it's kind of like more + +00:20:24.320 --> 00:20:27.080 +optional + +00:20:27.159 --> 00:20:30.159 +so + +00:20:44.039 --> 00:20:50.960 +yeah + +00:20:46.320 --> 00:20:53.960 +so it's it's definitely an empirical + +00:20:50.960 --> 00:20:53.960 +observation + +00:20:54.720 --> 00:21:01.080 +um in terms of the theoretical + +00:20:57.640 --> 00:21:03.120 +background I am not I can't immediately + +00:21:01.080 --> 00:21:05.840 +point to a + +00:21:03.120 --> 00:21:10.039 +particular paper that does that but I + +00:21:05.840 --> 00:21:12.720 +think if you think about + +00:21:10.039 --> 00:21:14.720 +the I I think I have seen that they do + +00:21:12.720 --> 00:21:17.039 +exist in the past but I I can't think of + +00:21:14.720 --> 00:21:19.000 +it right now I can try to uh try to come + +00:21:17.039 --> 00:21:23.720 +up with an example of + +00:21:19.000 --> 00:21:23.720 +that so yeah I I should take + +00:21:26.799 --> 00:21:31.960 +notes or someone wants to share one on + +00:21:29.360 --> 00:21:33.360 +Piaza uh if you have any ideas and want + +00:21:31.960 --> 00:21:34.520 +to share on Patza I'm sure that would be + +00:21:33.360 --> 00:21:35.640 +great it'd be great to have a discussion + +00:21:34.520 --> 00:21:39.320 +on + +00:21:35.640 --> 00:21:44.960 +Patza um Pi + +00:21:39.320 --> 00:21:46.880 +one cool okay so next I want to try to + +00:21:44.960 --> 00:21:48.200 +make a rule-based system and I'm going + +00:21:46.880 --> 00:21:49.360 +to make a rule-based system for + +00:21:48.200 --> 00:21:51.799 +sentiment + +00:21:49.360 --> 00:21:53.480 +analysis uh and this is a bad idea I + +00:21:51.799 --> 00:21:55.400 +would not encourage you to ever do this + +00:21:53.480 --> 00:21:57.440 +in real life but I want to do it here to + +00:21:55.400 --> 00:21:59.640 +show you why it's a bad idea and like + +00:21:57.440 --> 00:22:01.200 +what are some of the hard problems that + +00:21:59.640 --> 00:22:03.960 +you encounter when trying to create a + +00:22:01.200 --> 00:22:06.600 +system based on rules + +00:22:03.960 --> 00:22:08.080 +and then we'll move into building a + +00:22:06.600 --> 00:22:12.360 +machine learning base system after we + +00:22:08.080 --> 00:22:15.400 +finish this so if we look at the example + +00:22:12.360 --> 00:22:18.559 +test this is review sentiment analysis + +00:22:15.400 --> 00:22:21.799 +it's one of the most valuable uh tasks + +00:22:18.559 --> 00:22:24.039 +uh that people do in NLP nowadays + +00:22:21.799 --> 00:22:26.400 +because it allows people to know how + +00:22:24.039 --> 00:22:29.200 +customers are thinking about products uh + +00:22:26.400 --> 00:22:30.799 +improve their you know their product + +00:22:29.200 --> 00:22:32.919 +development and other things like that + +00:22:30.799 --> 00:22:34.799 +may monitor people's you know + +00:22:32.919 --> 00:22:36.760 +satisfaction with their social media + +00:22:34.799 --> 00:22:39.200 +service other things like this so + +00:22:36.760 --> 00:22:42.720 +basically the way it works is um you + +00:22:39.200 --> 00:22:44.400 +have uh outputs or you have sentences + +00:22:42.720 --> 00:22:46.720 +inputs like I hate this movie I love + +00:22:44.400 --> 00:22:48.520 +this movie I saw this movie and this + +00:22:46.720 --> 00:22:50.600 +gets mapped into positive neutral or + +00:22:48.520 --> 00:22:53.120 +negative so I hate this movie would be + +00:22:50.600 --> 00:22:55.480 +negative I love this movie positive and + +00:22:53.120 --> 00:22:59.039 +I saw this movie is + +00:22:55.480 --> 00:23:01.200 +neutral so um + +00:22:59.039 --> 00:23:05.200 +that that's the task input tax output + +00:23:01.200 --> 00:23:08.880 +labels uh Kary uh sentence + +00:23:05.200 --> 00:23:11.679 +label and in order to do this uh we + +00:23:08.880 --> 00:23:13.120 +would like to build a model um and we're + +00:23:11.679 --> 00:23:16.159 +going to build the model in a rule based + +00:23:13.120 --> 00:23:19.000 +way but it we'll still call it a model + +00:23:16.159 --> 00:23:21.600 +and the way it works is we do feature + +00:23:19.000 --> 00:23:23.159 +extraction um so we extract the Salient + +00:23:21.600 --> 00:23:25.279 +features for making the decision about + +00:23:23.159 --> 00:23:27.320 +what to Output next we do score + +00:23:25.279 --> 00:23:29.880 +calculation calculate a score for one or + +00:23:27.320 --> 00:23:32.320 +more possib ities and we have a decision + +00:23:29.880 --> 00:23:33.520 +function so we choose one of those + +00:23:32.320 --> 00:23:37.679 +several + +00:23:33.520 --> 00:23:40.120 +possibilities and so for feature + +00:23:37.679 --> 00:23:42.200 +extraction uh formally what this looks + +00:23:40.120 --> 00:23:44.240 +like is we have some function and it + +00:23:42.200 --> 00:23:48.039 +extracts a feature + +00:23:44.240 --> 00:23:51.159 +Vector for score calculation um we + +00:23:48.039 --> 00:23:54.240 +calculate the scores based on either a + +00:23:51.159 --> 00:23:56.279 +binary classification uh where we have a + +00:23:54.240 --> 00:23:58.279 +a weight vector and we take the dot + +00:23:56.279 --> 00:24:00.120 +product with our feature vector or we + +00:23:58.279 --> 00:24:02.480 +have multi class classification where we + +00:24:00.120 --> 00:24:04.520 +have a weight Matrix and we take the + +00:24:02.480 --> 00:24:08.640 +product with uh the vector and that + +00:24:04.520 --> 00:24:08.640 +gives us you know squares over multiple + +00:24:08.919 --> 00:24:14.840 +classes and then we have a decision uh + +00:24:11.600 --> 00:24:17.520 +rule so this decision rule tells us what + +00:24:14.840 --> 00:24:20.080 +the output is going to be um does anyone + +00:24:17.520 --> 00:24:22.200 +know what a typical decision rule is + +00:24:20.080 --> 00:24:24.520 +maybe maybe so obvious that you don't + +00:24:22.200 --> 00:24:28.760 +think about it often + +00:24:24.520 --> 00:24:31.000 +but uh a threshold um so like for would + +00:24:28.760 --> 00:24:34.440 +that be for binary a single binary + +00:24:31.000 --> 00:24:37.000 +scaler score or a multiple + +00:24:34.440 --> 00:24:38.520 +class binary yeah so and then you would + +00:24:37.000 --> 00:24:39.960 +pick a threshold and if it's over the + +00:24:38.520 --> 00:24:42.919 +threshold + +00:24:39.960 --> 00:24:45.760 +you say yes and if it's under the + +00:24:42.919 --> 00:24:50.279 +threshold you say no um another option + +00:24:45.760 --> 00:24:51.679 +would be um you have a threshold and you + +00:24:50.279 --> 00:24:56.080 +say + +00:24:51.679 --> 00:24:56.080 +yes no + +00:24:56.200 --> 00:25:00.559 +obain so you know you don't give an + +00:24:58.360 --> 00:25:02.520 +answer and depending on how you're + +00:25:00.559 --> 00:25:03.720 +evaluated what what is a good classifier + +00:25:02.520 --> 00:25:07.799 +you might want to abstain some of the + +00:25:03.720 --> 00:25:10.960 +time also um for multiclass what what's + +00:25:07.799 --> 00:25:10.960 +a standard decision role for + +00:25:11.120 --> 00:25:16.720 +multiclass argmax yeah exactly so um + +00:25:14.279 --> 00:25:19.520 +basically you you find the index that + +00:25:16.720 --> 00:25:22.000 +has the highest score in you output + +00:25:19.520 --> 00:25:24.480 +it we're going to be talking about other + +00:25:22.000 --> 00:25:26.559 +decision rules also um like + +00:25:24.480 --> 00:25:29.480 +self-consistency and minimum based risk + +00:25:26.559 --> 00:25:30.760 +later uh for text generation so you can + +00:25:29.480 --> 00:25:33.000 +just keep that in mind and then we'll + +00:25:30.760 --> 00:25:36.279 +forget about it for like several + +00:25:33.000 --> 00:25:39.559 +classes um so for sentiment + +00:25:36.279 --> 00:25:42.159 +class um I have a Cod + +00:25:39.559 --> 00:25:45.159 +walk + +00:25:42.159 --> 00:25:45.159 +here + +00:25:46.240 --> 00:25:54.320 +and this is pretty simple um but if + +00:25:50.320 --> 00:25:58.559 +you're bored uh of the class and would + +00:25:54.320 --> 00:26:01.000 +like to um try out yourself you can + +00:25:58.559 --> 00:26:04.480 +Challenge and try to get a better score + +00:26:01.000 --> 00:26:06.120 +than I do um over the next few minutes + +00:26:04.480 --> 00:26:06.880 +but we have this rule based classifier + +00:26:06.120 --> 00:26:10.240 +in + +00:26:06.880 --> 00:26:12.640 +here and I will open it up in my vs + +00:26:10.240 --> 00:26:15.360 +code + +00:26:12.640 --> 00:26:18.360 +to try to create a rule-based classifier + +00:26:15.360 --> 00:26:18.360 +and basically the way this + +00:26:22.799 --> 00:26:29.960 +works is + +00:26:25.159 --> 00:26:29.960 +that we have a feature + +00:26:31.720 --> 00:26:37.720 +extraction we have feature extraction we + +00:26:34.120 --> 00:26:40.679 +have scoring and we have um a decision + +00:26:37.720 --> 00:26:43.480 +rle so here for our feature extraction I + +00:26:40.679 --> 00:26:44.720 +have created a list of good words and a + +00:26:43.480 --> 00:26:46.720 +list of bad + +00:26:44.720 --> 00:26:48.960 +words + +00:26:46.720 --> 00:26:51.320 +and what we do is we just count the + +00:26:48.960 --> 00:26:53.000 +number of good words that appeared and + +00:26:51.320 --> 00:26:55.320 +count the number of bad words that + +00:26:53.000 --> 00:26:57.880 +appeared then we also have a bias + +00:26:55.320 --> 00:27:01.159 +feature so the bias feature is a feature + +00:26:57.880 --> 00:27:03.679 +that's always one and so what that + +00:27:01.159 --> 00:27:06.799 +results in is we have a dimension three + +00:27:03.679 --> 00:27:08.880 +feature Vector um where this is like the + +00:27:06.799 --> 00:27:11.320 +number of good words this is the number + +00:27:08.880 --> 00:27:15.320 +of bad words and then you have the + +00:27:11.320 --> 00:27:17.760 +bias and then I also Define the feature + +00:27:15.320 --> 00:27:20.039 +weights that so for every good word we + +00:27:17.760 --> 00:27:22.200 +add one to our score for every bad word + +00:27:20.039 --> 00:27:25.559 +we add uh we subtract one from our score + +00:27:22.200 --> 00:27:29.399 +and for the BIOS we absor and so we then + +00:27:25.559 --> 00:27:30.480 +take the dot product between + +00:27:29.399 --> 00:27:34.360 +these + +00:27:30.480 --> 00:27:36.919 +two and we get minus + +00:27:34.360 --> 00:27:37.640 +0.5 and that gives us uh that gives us + +00:27:36.919 --> 00:27:41.000 +the + +00:27:37.640 --> 00:27:46.000 +squore so let's run + +00:27:41.000 --> 00:27:50.320 +that um and I read in some + +00:27:46.000 --> 00:27:52.600 +data and what this data looks like is + +00:27:50.320 --> 00:27:55.000 +basically we have a + +00:27:52.600 --> 00:27:57.559 +review um which says the rock is + +00:27:55.000 --> 00:27:59.480 +destined to be the 21st Century's new + +00:27:57.559 --> 00:28:01.240 +Conan and that he's going to make a + +00:27:59.480 --> 00:28:03.600 +splash even greater than Arnold + +00:28:01.240 --> 00:28:07.000 +Schwarzenegger jeanclaude vanam or + +00:28:03.600 --> 00:28:09.519 +Steven Seagal um so this seems pretty + +00:28:07.000 --> 00:28:10.840 +positive right I like that's a pretty + +00:28:09.519 --> 00:28:13.200 +high order to be better than Arnold + +00:28:10.840 --> 00:28:16.080 +Schwarzenegger or John Claude vanam uh + +00:28:13.200 --> 00:28:19.519 +if you're familiar with action movies um + +00:28:16.080 --> 00:28:22.840 +and so of course this gets a positive + +00:28:19.519 --> 00:28:24.120 +label and so uh we have run classifier + +00:28:22.840 --> 00:28:25.240 +actually maybe I should call this + +00:28:24.120 --> 00:28:27.600 +decision rule because this is + +00:28:25.240 --> 00:28:29.120 +essentially our decision Rule and here + +00:28:27.600 --> 00:28:32.600 +basically do the thing that I mentioned + +00:28:29.120 --> 00:28:35.440 +here the yes no obstain or in this case + +00:28:32.600 --> 00:28:38.360 +positive negative neutral so if the + +00:28:35.440 --> 00:28:40.159 +score is greater than zero we uh return + +00:28:38.360 --> 00:28:42.480 +one if the score is less than zero we + +00:28:40.159 --> 00:28:44.679 +return negative one which is negative + +00:28:42.480 --> 00:28:47.240 +and otherwise we returns + +00:28:44.679 --> 00:28:48.760 +zero um we have an accuracy calculation + +00:28:47.240 --> 00:28:51.519 +function just calculating the outputs + +00:28:48.760 --> 00:28:55.840 +are good and + +00:28:51.519 --> 00:28:57.440 +um this is uh the overall label count in + +00:28:55.840 --> 00:28:59.919 +the in the output so we can see there + +00:28:57.440 --> 00:29:03.120 +slightly more positives than there are + +00:28:59.919 --> 00:29:06.080 +negatives and then we can run this and + +00:29:03.120 --> 00:29:10.200 +we get a a score of + +00:29:06.080 --> 00:29:14.760 +43 and so one one thing that I have + +00:29:10.200 --> 00:29:19.279 +found um is I I do a lot of kind + +00:29:14.760 --> 00:29:21.240 +of research on how to make NLP systems + +00:29:19.279 --> 00:29:23.600 +better and one of the things I found + +00:29:21.240 --> 00:29:26.679 +really invaluable + +00:29:23.600 --> 00:29:27.840 +is if you're in a situation where you + +00:29:26.679 --> 00:29:29.720 +have a + +00:29:27.840 --> 00:29:31.760 +set task and you just want to make the + +00:29:29.720 --> 00:29:33.760 +system better on the set task doing + +00:29:31.760 --> 00:29:35.159 +comprehensive error analysis and + +00:29:33.760 --> 00:29:37.320 +understanding where your system is + +00:29:35.159 --> 00:29:39.880 +failing is one of the best ways to do + +00:29:37.320 --> 00:29:42.200 +that and I would like to do a very + +00:29:39.880 --> 00:29:43.640 +rudimentary version of this here and + +00:29:42.200 --> 00:29:46.519 +what I'm doing essentially is I'm just + +00:29:43.640 --> 00:29:47.480 +randomly picking uh several examples + +00:29:46.519 --> 00:29:49.320 +that were + +00:29:47.480 --> 00:29:52.000 +correct + +00:29:49.320 --> 00:29:54.840 +um and so like let let's look at the + +00:29:52.000 --> 00:29:58.200 +examples here um here the true label is + +00:29:54.840 --> 00:30:00.760 +zero um in this predicted one um it may + +00:29:58.200 --> 00:30:03.440 +not be as cutting as Woody or as true as + +00:30:00.760 --> 00:30:05.039 +back in the Glory Days of uh weekend and + +00:30:03.440 --> 00:30:07.440 +two or three things that I know about + +00:30:05.039 --> 00:30:09.640 +her but who else engaged in film Mak + +00:30:07.440 --> 00:30:12.679 +today is so cognizant of the cultural + +00:30:09.640 --> 00:30:14.480 +and moral issues involved in the process + +00:30:12.679 --> 00:30:17.600 +so what words in here are a good + +00:30:14.480 --> 00:30:20.840 +indication that this is a neutral + +00:30:17.600 --> 00:30:20.840 +sentence any + +00:30:23.760 --> 00:30:28.399 +ideas little bit tough + +00:30:26.240 --> 00:30:30.919 +huh starting to think maybe we should be + +00:30:28.399 --> 00:30:30.919 +using machine + +00:30:31.480 --> 00:30:37.440 +learning + +00:30:34.080 --> 00:30:40.320 +um even by the intentionally low + +00:30:37.440 --> 00:30:41.559 +standards of fratboy humor sority boys + +00:30:40.320 --> 00:30:43.840 +is a + +00:30:41.559 --> 00:30:46.080 +Bowser I think frat boy is maybe + +00:30:43.840 --> 00:30:47.360 +negative sentiment if you're familiar + +00:30:46.080 --> 00:30:50.360 +with + +00:30:47.360 --> 00:30:51.960 +us us I don't have any negative + +00:30:50.360 --> 00:30:54.519 +sentiment but the people who say it that + +00:30:51.960 --> 00:30:55.960 +way have negative senent maybe so if we + +00:30:54.519 --> 00:31:01.080 +wanted to go in and do that we could + +00:30:55.960 --> 00:31:01.080 +maybe I won't save this but + +00:31:01.519 --> 00:31:08.919 +uh + +00:31:04.240 --> 00:31:11.840 +um oh whoops I'll go back and fix it uh + +00:31:08.919 --> 00:31:14.840 +crass crass is pretty obviously negative + +00:31:11.840 --> 00:31:14.840 +right so I can add + +00:31:17.039 --> 00:31:21.080 +crass actually let me just add + +00:31:21.760 --> 00:31:29.159 +CR and then um I'll go back and have our + +00:31:26.559 --> 00:31:29.159 +train accurate + +00:31:32.159 --> 00:31:36.240 +wa maybe maybe I need to run the whole + +00:31:33.960 --> 00:31:36.240 +thing + +00:31:36.960 --> 00:31:39.960 +again + +00:31:40.960 --> 00:31:45.880 +and that budg the training accuracy a + +00:31:43.679 --> 00:31:50.360 +little um the dev test accuracy not very + +00:31:45.880 --> 00:31:53.919 +much so I could go through and do this + +00:31:50.360 --> 00:31:53.919 +um let me add + +00:31:54.000 --> 00:31:58.320 +unengaging so I could go through and do + +00:31:56.000 --> 00:32:01.720 +this all day and you probably be very + +00:31:58.320 --> 00:32:01.720 +bored on + +00:32:04.240 --> 00:32:08.360 +engage but I won't do that uh because we + +00:32:06.919 --> 00:32:10.679 +have much more important things to be + +00:32:08.360 --> 00:32:14.679 +doing + +00:32:10.679 --> 00:32:16.440 +um and uh so anyway we um we could go + +00:32:14.679 --> 00:32:18.919 +through and design all the features here + +00:32:16.440 --> 00:32:21.279 +but like why is this complicated like + +00:32:18.919 --> 00:32:22.600 +the the reason why it was complicated + +00:32:21.279 --> 00:32:25.840 +became pretty + +00:32:22.600 --> 00:32:27.840 +clear from the uh from the very + +00:32:25.840 --> 00:32:29.639 +beginning uh the very first example I + +00:32:27.840 --> 00:32:32.200 +showed you which was that was a really + +00:32:29.639 --> 00:32:34.720 +complicated sentence like all of us + +00:32:32.200 --> 00:32:36.240 +could see that it wasn't like really + +00:32:34.720 --> 00:32:38.679 +strongly positive it wasn't really + +00:32:36.240 --> 00:32:40.519 +strongly negative it was kind of like in + +00:32:38.679 --> 00:32:42.919 +the middle but it was in the middle and + +00:32:40.519 --> 00:32:44.600 +it said it in a very long way uh you + +00:32:42.919 --> 00:32:46.120 +know not using any clearly positive + +00:32:44.600 --> 00:32:47.639 +sentiment words not using any clearly + +00:32:46.120 --> 00:32:49.760 +negative sentiment + +00:32:47.639 --> 00:32:53.760 +words + +00:32:49.760 --> 00:32:56.519 +um so yeah basically I I + +00:32:53.760 --> 00:33:00.559 +improved um but what are the difficult + +00:32:56.519 --> 00:33:03.720 +cases uh that we saw here so the first + +00:33:00.559 --> 00:33:07.639 +one is low frequency + +00:33:03.720 --> 00:33:09.760 +words so um here's an example the action + +00:33:07.639 --> 00:33:11.519 +switches between past and present but + +00:33:09.760 --> 00:33:13.120 +the material link is too tenuous to + +00:33:11.519 --> 00:33:16.840 +Anchor the emotional connections at + +00:33:13.120 --> 00:33:19.519 +purport to span a 125 year divide so + +00:33:16.840 --> 00:33:21.080 +this is negative um tenuous is kind of a + +00:33:19.519 --> 00:33:22.799 +negative word purport is kind of a + +00:33:21.080 --> 00:33:24.760 +negative word but it doesn't appear very + +00:33:22.799 --> 00:33:26.159 +frequently so I would need to spend all + +00:33:24.760 --> 00:33:29.720 +my time looking for these words and + +00:33:26.159 --> 00:33:32.480 +trying to them in um here's yet another + +00:33:29.720 --> 00:33:34.240 +horse franchise mucking up its storyline + +00:33:32.480 --> 00:33:36.639 +with glitches casual fans could correct + +00:33:34.240 --> 00:33:40.159 +in their sleep negative + +00:33:36.639 --> 00:33:42.600 +again um so the solutions here are keep + +00:33:40.159 --> 00:33:46.880 +working until we get all of them which + +00:33:42.600 --> 00:33:49.159 +is maybe not super fun um or incorporate + +00:33:46.880 --> 00:33:51.639 +external resources such as sentiment + +00:33:49.159 --> 00:33:52.880 +dictionaries that people created uh we + +00:33:51.639 --> 00:33:55.960 +could do that but that's a lot of + +00:33:52.880 --> 00:33:57.480 +engineering effort to make something + +00:33:55.960 --> 00:34:00.639 +work + +00:33:57.480 --> 00:34:03.720 +um another one is conjugation so we saw + +00:34:00.639 --> 00:34:06.600 +unengaging I guess that's an example of + +00:34:03.720 --> 00:34:08.359 +conjugation uh some other ones are + +00:34:06.600 --> 00:34:10.520 +operatic sprawling picture that's + +00:34:08.359 --> 00:34:12.040 +entertainingly acted magnificently shot + +00:34:10.520 --> 00:34:15.480 +and gripping enough to sustain most of + +00:34:12.040 --> 00:34:17.399 +its 170 minute length so here we have + +00:34:15.480 --> 00:34:19.079 +magnificently so even if I added + +00:34:17.399 --> 00:34:20.480 +magnificent this wouldn't have been + +00:34:19.079 --> 00:34:23.800 +clocked + +00:34:20.480 --> 00:34:26.599 +right um it's basically an overlong + +00:34:23.800 --> 00:34:28.839 +episode of tales from the cryp so that's + +00:34:26.599 --> 00:34:31.480 +maybe another + +00:34:28.839 --> 00:34:33.040 +example um so some things that we could + +00:34:31.480 --> 00:34:35.320 +do or what we would have done before the + +00:34:33.040 --> 00:34:37.720 +modern Paradigm of machine learning is + +00:34:35.320 --> 00:34:40.079 +we would run some sort of normalizer + +00:34:37.720 --> 00:34:42.800 +like a stemmer or other things like this + +00:34:40.079 --> 00:34:45.240 +in order to convert this into uh the + +00:34:42.800 --> 00:34:48.599 +root wordss that we already have seen + +00:34:45.240 --> 00:34:52.040 +somewhere in our data or have already + +00:34:48.599 --> 00:34:54.040 +handed so that requires um conjugation + +00:34:52.040 --> 00:34:55.879 +analysis or morphological analysis as we + +00:34:54.040 --> 00:34:57.400 +say it in + +00:34:55.879 --> 00:35:00.680 +technicals + +00:34:57.400 --> 00:35:03.960 +negation this is a tricky one so this + +00:35:00.680 --> 00:35:06.760 +one's not nearly as Dreadful as expected + +00:35:03.960 --> 00:35:08.800 +so Dreadful is a pretty bad word right + +00:35:06.760 --> 00:35:13.000 +but not nearly as Dreadful as expected + +00:35:08.800 --> 00:35:14.440 +is like a solidly neutral um you know or + +00:35:13.000 --> 00:35:16.359 +maybe even + +00:35:14.440 --> 00:35:18.920 +positive I would I would say that's + +00:35:16.359 --> 00:35:20.640 +neutral but you know uh neutral or + +00:35:18.920 --> 00:35:23.800 +positive it's definitely not + +00:35:20.640 --> 00:35:26.359 +negative um serving s doesn't serve up a + +00:35:23.800 --> 00:35:29.480 +whole lot of laughs so laughs is + +00:35:26.359 --> 00:35:31.880 +obviously positive but not serving UPS + +00:35:29.480 --> 00:35:34.440 +is obviously + +00:35:31.880 --> 00:35:36.839 +negative so if negation modifies the + +00:35:34.440 --> 00:35:38.240 +word disregard it now we would probably + +00:35:36.839 --> 00:35:41.440 +need to do some sort of syntactic + +00:35:38.240 --> 00:35:45.599 +analysis or semantic analysis of + +00:35:41.440 --> 00:35:47.520 +some metaphor an analogy so puts a human + +00:35:45.599 --> 00:35:50.640 +face on a land most westerners are + +00:35:47.520 --> 00:35:52.880 +unfamiliar though uh this is + +00:35:50.640 --> 00:35:54.960 +positive green might want to hang on to + +00:35:52.880 --> 00:35:58.800 +that ski mask as robbery may be the only + +00:35:54.960 --> 00:35:58.800 +way to pay for this next project + +00:35:58.839 --> 00:36:03.640 +so this this is saying that the movie + +00:36:01.960 --> 00:36:05.560 +was so bad that the director will have + +00:36:03.640 --> 00:36:08.359 +to rob people in order to get money for + +00:36:05.560 --> 00:36:11.000 +the next project so that's kind of bad I + +00:36:08.359 --> 00:36:12.880 +guess um has all the depth of a waiting + +00:36:11.000 --> 00:36:14.520 +pool this is kind of my favorite one + +00:36:12.880 --> 00:36:15.880 +because it's really short and sweet but + +00:36:14.520 --> 00:36:18.800 +you know you need to know how deep a + +00:36:15.880 --> 00:36:21.440 +waiting pool is um so that's + +00:36:18.800 --> 00:36:22.960 +negative so the solution here I don't + +00:36:21.440 --> 00:36:24.680 +really even know how to handle this with + +00:36:22.960 --> 00:36:26.880 +a rule based system I have no idea how + +00:36:24.680 --> 00:36:30.040 +we would possibly do this yeah machine + +00:36:26.880 --> 00:36:32.400 +learning based models seem to be pretty + +00:36:30.040 --> 00:36:37.000 +adaptive okay and then I start doing + +00:36:32.400 --> 00:36:37.000 +these ones um anyone have a good + +00:36:38.160 --> 00:36:46.800 +idea any any other friends who know + +00:36:42.520 --> 00:36:50.040 +Japanese no okay um so yeah that's + +00:36:46.800 --> 00:36:52.839 +positive um that one's negative uh and + +00:36:50.040 --> 00:36:54.920 +the solution here is learn Japanese I + +00:36:52.839 --> 00:36:56.800 +guess or whatever other language you + +00:36:54.920 --> 00:37:00.040 +want to process so like obviously + +00:36:56.800 --> 00:37:03.720 +rule-based systems don't scale very + +00:37:00.040 --> 00:37:05.119 +well so um we've moved but like rule + +00:37:03.720 --> 00:37:06.319 +based systems don't scale very well + +00:37:05.119 --> 00:37:08.160 +we're not going to be using them for + +00:37:06.319 --> 00:37:11.400 +most of the things we do in this class + +00:37:08.160 --> 00:37:14.240 +but I do think it's sometimes useful to + +00:37:11.400 --> 00:37:15.640 +try to create one for your task maybe + +00:37:14.240 --> 00:37:16.680 +right at the very beginning of a project + +00:37:15.640 --> 00:37:18.560 +because it gives you an idea about + +00:37:16.680 --> 00:37:21.160 +what's really hard about the task in + +00:37:18.560 --> 00:37:22.480 +some cases so um yeah I wouldn't + +00:37:21.160 --> 00:37:25.599 +entirely discount them I'm not + +00:37:22.480 --> 00:37:27.400 +introducing them for no reason + +00:37:25.599 --> 00:37:29.880 +whatsoever + +00:37:27.400 --> 00:37:34.160 +so next is machine learning based anal + +00:37:29.880 --> 00:37:35.400 +and machine learning uh in general uh I + +00:37:34.160 --> 00:37:36.640 +here actually when I say machine + +00:37:35.400 --> 00:37:38.160 +learning I'm going to be talking about + +00:37:36.640 --> 00:37:39.560 +the traditional fine-tuning approach + +00:37:38.160 --> 00:37:43.520 +where we have a training set Dev set + +00:37:39.560 --> 00:37:46.359 +test set and so we take our training set + +00:37:43.520 --> 00:37:49.680 +we run some learning algorithm over it + +00:37:46.359 --> 00:37:52.319 +we have a learned feature extractor F A + +00:37:49.680 --> 00:37:55.839 +possibly learned feature extractor F + +00:37:52.319 --> 00:37:57.880 +possibly learned scoring function W and + +00:37:55.839 --> 00:38:00.800 +uh then we apply our inference algorithm + +00:37:57.880 --> 00:38:02.839 +our decision Rule and make decisions + +00:38:00.800 --> 00:38:04.200 +when I say possibly learned actually the + +00:38:02.839 --> 00:38:06.119 +first example I'm going to give of a + +00:38:04.200 --> 00:38:07.760 +machine learning based technique is uh + +00:38:06.119 --> 00:38:10.079 +doesn't have a learned feature extractor + +00:38:07.760 --> 00:38:12.800 +but most things that we use nowadays do + +00:38:10.079 --> 00:38:12.800 +have learned feature + +00:38:13.200 --> 00:38:18.040 +extractors so our first attempt is going + +00:38:15.640 --> 00:38:21.760 +to be a bag of words model uh and the + +00:38:18.040 --> 00:38:27.119 +way a bag of wordss model works is uh + +00:38:21.760 --> 00:38:30.160 +essentially we start out by looking up a + +00:38:27.119 --> 00:38:33.240 +Vector where one element in the vector + +00:38:30.160 --> 00:38:36.240 +is uh is one and all the other elements + +00:38:33.240 --> 00:38:38.040 +in the vector are zero and so if the + +00:38:36.240 --> 00:38:40.319 +word is different the position in the + +00:38:38.040 --> 00:38:42.839 +vector that's one will be different we + +00:38:40.319 --> 00:38:46.280 +add all of these together and this gives + +00:38:42.839 --> 00:38:48.200 +us a vector where each element is the + +00:38:46.280 --> 00:38:50.359 +frequency of that word in the vector and + +00:38:48.200 --> 00:38:52.520 +then we multiply that by weights and we + +00:38:50.359 --> 00:38:55.520 +get a + +00:38:52.520 --> 00:38:57.160 +score and um here as I said this is not + +00:38:55.520 --> 00:39:00.359 +a learned feature + +00:38:57.160 --> 00:39:02.079 +uh Vector this is basically uh sorry not + +00:39:00.359 --> 00:39:04.359 +a learn feature extractor this is + +00:39:02.079 --> 00:39:06.200 +basically a fixed feature extractor but + +00:39:04.359 --> 00:39:09.839 +the weights themselves are + +00:39:06.200 --> 00:39:11.640 +learned um so my my question is I + +00:39:09.839 --> 00:39:14.599 +mentioned a whole lot of problems before + +00:39:11.640 --> 00:39:17.480 +I mentioned infrequent words I mentioned + +00:39:14.599 --> 00:39:20.760 +conjugation I mentioned uh different + +00:39:17.480 --> 00:39:22.880 +languages I mentioned syntax and + +00:39:20.760 --> 00:39:24.599 +metaphor so which of these do we think + +00:39:22.880 --> 00:39:25.440 +would be fixed by this sort of learning + +00:39:24.599 --> 00:39:27.400 +based + +00:39:25.440 --> 00:39:29.640 +approach + +00:39:27.400 --> 00:39:29.640 +any + +00:39:29.920 --> 00:39:35.200 +ideas maybe not fixed maybe made + +00:39:32.520 --> 00:39:35.200 +significantly + +00:39:36.880 --> 00:39:41.560 +better any Brave uh brave + +00:39:44.880 --> 00:39:48.440 +people maybe maybe + +00:39:53.720 --> 00:39:58.400 +negation okay so maybe doesn't when it + +00:39:55.760 --> 00:39:58.400 +have a negative qu + +00:40:02.960 --> 00:40:07.560 +yeah yeah so for the conjugation if we + +00:40:05.520 --> 00:40:09.200 +had the conjugations of the stems mapped + +00:40:07.560 --> 00:40:11.119 +in the same position that might fix a + +00:40:09.200 --> 00:40:12.920 +conjugation problem but I would say if + +00:40:11.119 --> 00:40:15.200 +you don't do that then this kind of + +00:40:12.920 --> 00:40:18.160 +fixes conjugation a little bit but maybe + +00:40:15.200 --> 00:40:21.319 +not not really yeah kind of fix + +00:40:18.160 --> 00:40:24.079 +conjugation because like they're using + +00:40:21.319 --> 00:40:26.760 +the same there + +00:40:24.079 --> 00:40:28.400 +probably different variations so we + +00:40:26.760 --> 00:40:31.359 +learn how to + +00:40:28.400 --> 00:40:33.400 +classify surrounding + +00:40:31.359 --> 00:40:35.000 +structure yeah if it's a big enough + +00:40:33.400 --> 00:40:36.760 +training set you might have covered the + +00:40:35.000 --> 00:40:37.880 +various conjugations but if you haven't + +00:40:36.760 --> 00:40:43.000 +and you don't have any rule-based + +00:40:37.880 --> 00:40:43.000 +processing it it might still be problems + +00:40:45.400 --> 00:40:50.359 +yeah yeah so in frequent words if you + +00:40:48.280 --> 00:40:52.560 +have a large enough training set yeah + +00:40:50.359 --> 00:40:54.599 +you'll be able to fix it to some extent + +00:40:52.560 --> 00:40:56.480 +so none of the problems are entirely + +00:40:54.599 --> 00:40:57.880 +fixed but a lot of them are made better + +00:40:56.480 --> 00:40:58.960 +different languages is also made better + +00:40:57.880 --> 00:41:00.119 +if you have training data in that + +00:40:58.960 --> 00:41:04.599 +language but if you don't then you're + +00:41:00.119 --> 00:41:06.240 +out of BL so um so now what I'd like to + +00:41:04.599 --> 00:41:10.800 +do is I'd look to like to look at what + +00:41:06.240 --> 00:41:15.079 +our vectors represent so basically um in + +00:41:10.800 --> 00:41:16.880 +uh in binary classification each word um + +00:41:15.079 --> 00:41:19.119 +sorry so the vectors themselves + +00:41:16.880 --> 00:41:21.880 +represent the counts of the words here + +00:41:19.119 --> 00:41:25.319 +I'm talking about what the weight uh + +00:41:21.880 --> 00:41:28.520 +vectors or matrices correspond to and + +00:41:25.319 --> 00:41:31.640 +the weight uh Vector here will be + +00:41:28.520 --> 00:41:33.680 +positive if the word it tends to be + +00:41:31.640 --> 00:41:36.680 +positive if in a binary classification + +00:41:33.680 --> 00:41:38.400 +case in a multiclass classification case + +00:41:36.680 --> 00:41:42.480 +we'll actually have a matrix that looks + +00:41:38.400 --> 00:41:45.480 +like this where um each column or row uh + +00:41:42.480 --> 00:41:47.079 +corresponds to the word and each row or + +00:41:45.480 --> 00:41:49.319 +column corresponds to a label and it + +00:41:47.079 --> 00:41:51.960 +will be higher if that row tends to uh + +00:41:49.319 --> 00:41:54.800 +correlate with that uh that word tends + +00:41:51.960 --> 00:41:56.920 +to correlate that little + +00:41:54.800 --> 00:41:59.240 +bit so + +00:41:56.920 --> 00:42:04.079 +this um training of the bag of words + +00:41:59.240 --> 00:42:07.720 +model is can be done uh so simply that + +00:42:04.079 --> 00:42:10.200 +we uh can put it in a single slide so + +00:42:07.720 --> 00:42:11.599 +basically here uh what we do is we start + +00:42:10.200 --> 00:42:14.760 +out with the feature + +00:42:11.599 --> 00:42:18.880 +weights and for each example in our data + +00:42:14.760 --> 00:42:20.800 +set we extract features um the exact way + +00:42:18.880 --> 00:42:23.920 +I'm extracting features is basically + +00:42:20.800 --> 00:42:25.720 +splitting uh splitting the words using + +00:42:23.920 --> 00:42:28.000 +the python split function and then uh + +00:42:25.720 --> 00:42:31.319 +Counting number of times each word + +00:42:28.000 --> 00:42:33.160 +exists uh we then run the classifier so + +00:42:31.319 --> 00:42:36.280 +actually running the classifier is + +00:42:33.160 --> 00:42:38.200 +exactly the same as what we did for the + +00:42:36.280 --> 00:42:42.640 +uh the rule based system it's just that + +00:42:38.200 --> 00:42:47.359 +we have feature vectors instead and + +00:42:42.640 --> 00:42:51.559 +then if the predicted value is + +00:42:47.359 --> 00:42:55.160 +not value then for each of the + +00:42:51.559 --> 00:42:56.680 +features uh in the feature space we + +00:42:55.160 --> 00:43:02.200 +upweight + +00:42:56.680 --> 00:43:03.599 +the um we upweight The Weight by the + +00:43:02.200 --> 00:43:06.000 +vector + +00:43:03.599 --> 00:43:09.920 +size by or by the amount of the vector + +00:43:06.000 --> 00:43:13.240 +if Y is positive and we downweight the + +00:43:09.920 --> 00:43:16.240 +vector uh by the size of the vector if Y + +00:43:13.240 --> 00:43:18.520 +is negative so this is really really + +00:43:16.240 --> 00:43:20.559 +simple it's uh probably the simplest + +00:43:18.520 --> 00:43:25.079 +possible algorithm for training one of + +00:43:20.559 --> 00:43:27.559 +these models um but I have an + +00:43:25.079 --> 00:43:30.040 +example in this that you can also take a + +00:43:27.559 --> 00:43:31.960 +look at here's a trained bag of words + +00:43:30.040 --> 00:43:33.680 +classifier and we could step through + +00:43:31.960 --> 00:43:34.960 +this is on exactly the same data set as + +00:43:33.680 --> 00:43:37.240 +I did before we're training on the + +00:43:34.960 --> 00:43:42.359 +training set + +00:43:37.240 --> 00:43:43.640 +um and uh evaluating on the dev set um I + +00:43:42.359 --> 00:43:45.880 +also have some extra stuff like I'm + +00:43:43.640 --> 00:43:47.079 +Shuffling the order of the data IDs + +00:43:45.880 --> 00:43:49.440 +which is really important if you're + +00:43:47.079 --> 00:43:53.160 +doing this sort of incremental algorithm + +00:43:49.440 --> 00:43:54.960 +uh because uh what if what if your + +00:43:53.160 --> 00:43:57.400 +creating data set was ordered in this + +00:43:54.960 --> 00:44:00.040 +way where you have all of the positive + +00:43:57.400 --> 00:44:00.040 +labels on + +00:44:00.359 --> 00:44:04.520 +top and then you have all of the + +00:44:02.280 --> 00:44:06.680 +negative labels on the + +00:44:04.520 --> 00:44:08.200 +bottom if you do something like this it + +00:44:06.680 --> 00:44:10.200 +would see only negative labels at the + +00:44:08.200 --> 00:44:11.800 +end of training and you might have + +00:44:10.200 --> 00:44:14.400 +problems because your model would only + +00:44:11.800 --> 00:44:17.440 +predict negatives so we also Shuffle + +00:44:14.400 --> 00:44:20.319 +data um and then step through we run the + +00:44:17.440 --> 00:44:22.559 +classifier and I'm going to run uh five + +00:44:20.319 --> 00:44:23.640 +epochs of training through the data set + +00:44:22.559 --> 00:44:27.160 +uh very + +00:44:23.640 --> 00:44:29.599 +fast and calculate our accuracy + +00:44:27.160 --> 00:44:33.280 +and this got 75% accuracy on the + +00:44:29.599 --> 00:44:36.160 +training data set and uh 56% accuracy on + +00:44:33.280 --> 00:44:40.000 +the Deb data set so uh if you remember + +00:44:36.160 --> 00:44:41.520 +our rule-based classifier had 42 uh 42 + +00:44:40.000 --> 00:44:43.880 +accuracy and now our training based + +00:44:41.520 --> 00:44:45.760 +classifier has 56 accuracy but it's + +00:44:43.880 --> 00:44:49.359 +overfitting heavily to the training side + +00:44:45.760 --> 00:44:50.880 +so um basically this is a pretty strong + +00:44:49.359 --> 00:44:53.480 +advertisement for why we should be using + +00:44:50.880 --> 00:44:54.960 +machine learning you know I the amount + +00:44:53.480 --> 00:44:57.800 +of code that we had for this machine + +00:44:54.960 --> 00:44:59.720 +learning model is basically very similar + +00:44:57.800 --> 00:45:02.680 +um it's not using any external libraries + +00:44:59.720 --> 00:45:02.680 +but we're getting better at + +00:45:03.599 --> 00:45:08.800 +this + +00:45:05.800 --> 00:45:08.800 +cool + +00:45:09.559 --> 00:45:16.000 +so cool any any questions + +00:45:13.520 --> 00:45:18.240 +here and so I'm going to talk about the + +00:45:16.000 --> 00:45:20.760 +connection to between this algorithm and + +00:45:18.240 --> 00:45:22.839 +neural networks in the next class um + +00:45:20.760 --> 00:45:24.200 +because this actually is using a very + +00:45:22.839 --> 00:45:26.319 +similar training algorithm to what we + +00:45:24.200 --> 00:45:27.480 +use in neural networks with some uh + +00:45:26.319 --> 00:45:30.079 +particular + +00:45:27.480 --> 00:45:32.839 +assumptions cool um so what's missing in + +00:45:30.079 --> 00:45:34.800 +bag of words um still handling of + +00:45:32.839 --> 00:45:36.880 +conjugation or compound words is not + +00:45:34.800 --> 00:45:39.160 +perfect it we can do it to some extent + +00:45:36.880 --> 00:45:41.079 +to the point where we can uh memorize + +00:45:39.160 --> 00:45:44.079 +things so I love this movie I love this + +00:45:41.079 --> 00:45:46.920 +movie another thing is handling word Ser + +00:45:44.079 --> 00:45:49.240 +uh similarities so I love this movie and + +00:45:46.920 --> 00:45:50.720 +I adore this movie uh these basically + +00:45:49.240 --> 00:45:52.119 +mean the same thing as humans we know + +00:45:50.720 --> 00:45:54.200 +they mean the same thing so we should be + +00:45:52.119 --> 00:45:56.079 +able to take advantage of that fact to + +00:45:54.200 --> 00:45:57.839 +learn better models but we're not doing + +00:45:56.079 --> 00:46:02.760 +that in this model at the moment because + +00:45:57.839 --> 00:46:05.440 +each unit is uh treated as a atomic unit + +00:46:02.760 --> 00:46:08.040 +and there's no idea of + +00:46:05.440 --> 00:46:11.040 +similarity also handling of combination + +00:46:08.040 --> 00:46:12.760 +features so um I love this movie and I + +00:46:11.040 --> 00:46:14.920 +don't love this movie I hate this movie + +00:46:12.760 --> 00:46:17.079 +and I don't hate this movie actually + +00:46:14.920 --> 00:46:20.400 +this is a little bit tricky because + +00:46:17.079 --> 00:46:23.240 +negative words are slightly indicative + +00:46:20.400 --> 00:46:25.280 +of it being negative but actually what + +00:46:23.240 --> 00:46:28.119 +they do is they negate the other things + +00:46:25.280 --> 00:46:28.119 +that you're saying in the + +00:46:28.240 --> 00:46:36.559 +sentence + +00:46:30.720 --> 00:46:40.480 +so um like love is positive hate is + +00:46:36.559 --> 00:46:40.480 +negative but like don't + +00:46:50.359 --> 00:46:56.079 +love it's actually kind of like this + +00:46:52.839 --> 00:46:59.359 +right like um Love is very positive POS + +00:46:56.079 --> 00:47:01.760 +hate is very negative but don't love is + +00:46:59.359 --> 00:47:04.680 +like slightly less positive than don't + +00:47:01.760 --> 00:47:06.160 +hate right so um It's actually kind of + +00:47:04.680 --> 00:47:07.559 +tricky because you need to combine them + +00:47:06.160 --> 00:47:10.720 +together and figure out what's going on + +00:47:07.559 --> 00:47:12.280 +based on that another example that a lot + +00:47:10.720 --> 00:47:14.160 +of people might not think of immediately + +00:47:12.280 --> 00:47:17.880 +but is super super common in sentiment + +00:47:14.160 --> 00:47:20.160 +analysis or any other thing is butt so + +00:47:17.880 --> 00:47:22.599 +basically what but does is it throws + +00:47:20.160 --> 00:47:24.160 +away all the stuff that you said before + +00:47:22.599 --> 00:47:26.119 +um and you can just pay attention to the + +00:47:24.160 --> 00:47:29.000 +stuff that you saw beforehand so like we + +00:47:26.119 --> 00:47:30.440 +could even add this to our um like if + +00:47:29.000 --> 00:47:31.760 +you want to add this to your rule based + +00:47:30.440 --> 00:47:33.240 +classifier you can do that you just + +00:47:31.760 --> 00:47:34.640 +search for butt and delete everything + +00:47:33.240 --> 00:47:37.240 +before it and see if that inputs your + +00:47:34.640 --> 00:47:39.240 +accuracy might be might be a fun very + +00:47:37.240 --> 00:47:43.480 +quick thing + +00:47:39.240 --> 00:47:44.880 +to cool so the better solution which is + +00:47:43.480 --> 00:47:46.800 +what we're going to talk about for every + +00:47:44.880 --> 00:47:49.480 +other class other than uh other than + +00:47:46.800 --> 00:47:52.160 +this one is neural network models and + +00:47:49.480 --> 00:47:55.800 +basically uh what they do is they do a + +00:47:52.160 --> 00:47:59.400 +lookup of uh dense word embeddings so + +00:47:55.800 --> 00:48:02.520 +instead of looking up uh individual uh + +00:47:59.400 --> 00:48:04.640 +sparse uh vectors individual one hot + +00:48:02.520 --> 00:48:06.920 +vectors they look up dense word + +00:48:04.640 --> 00:48:09.680 +embeddings and then throw them into some + +00:48:06.920 --> 00:48:11.880 +complicated function to extract features + +00:48:09.680 --> 00:48:16.359 +and based on the features uh multiply by + +00:48:11.880 --> 00:48:18.280 +weights and get a score um and if you're + +00:48:16.359 --> 00:48:20.359 +doing text classification in the + +00:48:18.280 --> 00:48:22.520 +traditional way this is normally what + +00:48:20.359 --> 00:48:23.760 +you do um if you're doing text + +00:48:22.520 --> 00:48:25.960 +classification with something like + +00:48:23.760 --> 00:48:27.280 +prompting you're still actually doing + +00:48:25.960 --> 00:48:29.960 +this because you're calculating the + +00:48:27.280 --> 00:48:32.960 +score of the next word to predict and + +00:48:29.960 --> 00:48:34.720 +that's done in exactly the same way so + +00:48:32.960 --> 00:48:37.760 +uh even if you're using a large language + +00:48:34.720 --> 00:48:39.359 +model like GPT this is still probably + +00:48:37.760 --> 00:48:41.800 +happening under the hood unless open the + +00:48:39.359 --> 00:48:43.400 +eye invented something that very + +00:48:41.800 --> 00:48:45.559 +different in Alien than anything else + +00:48:43.400 --> 00:48:48.440 +that we know of but I I'm guessing that + +00:48:45.559 --> 00:48:48.440 +that propably hasn't + +00:48:48.480 --> 00:48:52.880 +happen um one nice thing about neural + +00:48:50.880 --> 00:48:54.480 +networks is neural networks + +00:48:52.880 --> 00:48:57.559 +theoretically are powerful enough to + +00:48:54.480 --> 00:49:00.000 +solve any task if you make them uh deep + +00:48:57.559 --> 00:49:01.160 +enough or wide enough uh like if you + +00:49:00.000 --> 00:49:04.520 +make them wide enough and then if you + +00:49:01.160 --> 00:49:06.799 +make them deep it also helps further so + +00:49:04.520 --> 00:49:08.079 +anytime somebody says well you can't + +00:49:06.799 --> 00:49:11.119 +just solve that problem with neural + +00:49:08.079 --> 00:49:13.240 +networks you know that they're lying + +00:49:11.119 --> 00:49:15.720 +basically because they theoretically can + +00:49:13.240 --> 00:49:17.359 +solve every problem uh but you have you + +00:49:15.720 --> 00:49:19.799 +have issues of data you have issues of + +00:49:17.359 --> 00:49:23.079 +other things like that so you know they + +00:49:19.799 --> 00:49:23.079 +don't just necessarily work + +00:49:23.119 --> 00:49:28.040 +outs cool um so the final thing I'd like + +00:49:26.400 --> 00:49:29.319 +to talk about is the road map going + +00:49:28.040 --> 00:49:31.319 +forward some of the things I'm going to + +00:49:29.319 --> 00:49:32.799 +cover in the class and some of the + +00:49:31.319 --> 00:49:35.200 +logistics + +00:49:32.799 --> 00:49:36.799 +issues so um the first thing I'm going + +00:49:35.200 --> 00:49:38.240 +to talk about in the class is language + +00:49:36.799 --> 00:49:40.559 +modeling fun + +00:49:38.240 --> 00:49:42.720 +fundamentals and uh so this could + +00:49:40.559 --> 00:49:44.240 +include language models uh that just + +00:49:42.720 --> 00:49:46.559 +predict the next words it could include + +00:49:44.240 --> 00:49:50.559 +language models that predict the output + +00:49:46.559 --> 00:49:51.599 +given the uh the input or the prompt um + +00:49:50.559 --> 00:49:54.559 +I'm going to be talking about + +00:49:51.599 --> 00:49:56.520 +representing words uh how how we get + +00:49:54.559 --> 00:49:59.319 +word representation subword models other + +00:49:56.520 --> 00:50:01.440 +things like that uh then go kind of + +00:49:59.319 --> 00:50:04.200 +deeper into language modeling uh how do + +00:50:01.440 --> 00:50:07.799 +we do it how do we evaluate it other + +00:50:04.200 --> 00:50:10.920 +things um sequence encoding uh and this + +00:50:07.799 --> 00:50:13.240 +is going to cover things like uh + +00:50:10.920 --> 00:50:16.280 +Transformers uh self attention modals + +00:50:13.240 --> 00:50:18.559 +but also very quickly cnns and rnns + +00:50:16.280 --> 00:50:20.880 +which are useful in some + +00:50:18.559 --> 00:50:22.200 +cases um and then we're going to + +00:50:20.880 --> 00:50:24.040 +specifically go very deep into the + +00:50:22.200 --> 00:50:25.960 +Transformer architecture and also talk a + +00:50:24.040 --> 00:50:27.280 +little bit about some of the modern uh + +00:50:25.960 --> 00:50:30.240 +improvements to the Transformer + +00:50:27.280 --> 00:50:31.839 +architecture so the Transformer we're + +00:50:30.240 --> 00:50:33.839 +using nowadays is very different than + +00:50:31.839 --> 00:50:36.200 +the Transformer that was invented in + +00:50:33.839 --> 00:50:37.240 +2017 uh so we're going to talk well I + +00:50:36.200 --> 00:50:38.760 +wouldn't say very different but + +00:50:37.240 --> 00:50:41.359 +different enough that it's important so + +00:50:38.760 --> 00:50:43.280 +we're going to talk about some of those + +00:50:41.359 --> 00:50:45.079 +things second thing I'd like to talk + +00:50:43.280 --> 00:50:47.000 +about is training and inference methods + +00:50:45.079 --> 00:50:48.839 +so this includes uh generation + +00:50:47.000 --> 00:50:52.119 +algorithms uh so we're going to have a + +00:50:48.839 --> 00:50:55.520 +whole class on how we generate text uh + +00:50:52.119 --> 00:50:58.319 +in different ways uh prompting how uh we + +00:50:55.520 --> 00:50:59.720 +can prompt things I hear uh world class + +00:50:58.319 --> 00:51:01.799 +prompt engineers make a lot of money + +00:50:59.720 --> 00:51:05.480 +nowadays so uh you'll want to pay + +00:51:01.799 --> 00:51:08.760 +attention to that one um and instruction + +00:51:05.480 --> 00:51:11.520 +tuning uh so how do we train models to + +00:51:08.760 --> 00:51:13.720 +handle a lot of different tasks and + +00:51:11.520 --> 00:51:15.839 +reinforcement learning so how do we uh + +00:51:13.720 --> 00:51:18.520 +you know like actually generate outputs + +00:51:15.839 --> 00:51:19.839 +uh kind of Judge them and then learn + +00:51:18.520 --> 00:51:22.599 +from + +00:51:19.839 --> 00:51:25.880 +there also experimental design and + +00:51:22.599 --> 00:51:28.079 +evaluation so experimental design uh so + +00:51:25.880 --> 00:51:30.480 +how do we design an experiment well uh + +00:51:28.079 --> 00:51:32.000 +so that it backs up what we want to be + +00:51:30.480 --> 00:51:34.559 +uh our conclusions that we want to be + +00:51:32.000 --> 00:51:37.000 +backing up how do we do human annotation + +00:51:34.559 --> 00:51:38.880 +of data in a reliable way this is + +00:51:37.000 --> 00:51:41.160 +getting harder and harder as models get + +00:51:38.880 --> 00:51:43.359 +better and better because uh getting + +00:51:41.160 --> 00:51:45.000 +humans who don't care very much about + +00:51:43.359 --> 00:51:48.559 +The annotation task they might do worse + +00:51:45.000 --> 00:51:51.119 +than gp4 so um you need to be careful of + +00:51:48.559 --> 00:51:52.240 +that also debugging and interpretation + +00:51:51.119 --> 00:51:53.960 +technique so what are some of the + +00:51:52.240 --> 00:51:55.160 +automatic techniques that you can do to + +00:51:53.960 --> 00:51:57.720 +quickly figure out what's going wrong + +00:51:55.160 --> 00:52:00.040 +with your models and improve + +00:51:57.720 --> 00:52:01.599 +them and uh bias and fairness + +00:52:00.040 --> 00:52:04.200 +considerations so it's really really + +00:52:01.599 --> 00:52:05.799 +important nowadays uh that models are + +00:52:04.200 --> 00:52:07.880 +being deployed to real people in the + +00:52:05.799 --> 00:52:09.880 +real world and like actually causing + +00:52:07.880 --> 00:52:11.760 +harm to people in some cases that we + +00:52:09.880 --> 00:52:15.160 +need to be worried about + +00:52:11.760 --> 00:52:17.000 +that Advanced Training in architectures + +00:52:15.160 --> 00:52:19.280 +so we're going to talk about distill + +00:52:17.000 --> 00:52:21.400 +distillation and quantization how can we + +00:52:19.280 --> 00:52:23.520 +make small language models uh that + +00:52:21.400 --> 00:52:24.880 +actually still work well like not large + +00:52:23.520 --> 00:52:27.559 +you can run them on your phone you can + +00:52:24.880 --> 00:52:29.920 +run them on your local + +00:52:27.559 --> 00:52:31.640 +laptop um ensembling and mixtures of + +00:52:29.920 --> 00:52:33.480 +experts how can we combine together + +00:52:31.640 --> 00:52:34.760 +multiple models in order to create + +00:52:33.480 --> 00:52:35.880 +models that are better than the sum of + +00:52:34.760 --> 00:52:38.799 +their + +00:52:35.880 --> 00:52:40.720 +parts and um retrieval and retrieval + +00:52:38.799 --> 00:52:43.920 +augmented + +00:52:40.720 --> 00:52:45.480 +generation long sequence models uh so + +00:52:43.920 --> 00:52:49.920 +how do we handle long + +00:52:45.480 --> 00:52:52.240 +outputs um and uh we're going to talk + +00:52:49.920 --> 00:52:55.760 +about applications to complex reasoning + +00:52:52.240 --> 00:52:57.760 +tasks code generation language agents + +00:52:55.760 --> 00:52:59.920 +and knowledge-based QA and information + +00:52:57.760 --> 00:53:04.160 +extraction I picked + +00:52:59.920 --> 00:53:06.760 +these because they seem to be maybe the + +00:53:04.160 --> 00:53:09.880 +most important at least in research + +00:53:06.760 --> 00:53:11.440 +nowadays and also they cover uh the + +00:53:09.880 --> 00:53:13.640 +things that when I talk to people in + +00:53:11.440 --> 00:53:15.280 +Industry are kind of most interested in + +00:53:13.640 --> 00:53:17.559 +so hopefully it'll be useful regardless + +00:53:15.280 --> 00:53:19.799 +of uh whether you plan on doing research + +00:53:17.559 --> 00:53:22.839 +or or plan on doing industry related + +00:53:19.799 --> 00:53:24.160 +things uh by by the way the two things + +00:53:22.839 --> 00:53:25.920 +that when I talk to people in Industry + +00:53:24.160 --> 00:53:29.599 +they're most interested in are Rag and + +00:53:25.920 --> 00:53:31.079 +code generation at the moment for now um + +00:53:29.599 --> 00:53:32.319 +so those are ones that you'll want to + +00:53:31.079 --> 00:53:34.680 +pay attention + +00:53:32.319 --> 00:53:36.599 +to and then finally we have a few + +00:53:34.680 --> 00:53:40.079 +lectures on Linguistics and + +00:53:36.599 --> 00:53:42.720 +multilinguality um I love Linguistics + +00:53:40.079 --> 00:53:44.839 +but uh to be honest at the moment most + +00:53:42.720 --> 00:53:47.760 +of our Cutting Edge models don't + +00:53:44.839 --> 00:53:49.240 +explicitly use linguistic structure um + +00:53:47.760 --> 00:53:50.799 +but I still think it's useful to know + +00:53:49.240 --> 00:53:52.760 +about it especially if you're working on + +00:53:50.799 --> 00:53:54.880 +multilingual things especially if you're + +00:53:52.760 --> 00:53:57.040 +interested in very robust generalization + +00:53:54.880 --> 00:53:58.920 +to new models so we're going to talk a + +00:53:57.040 --> 00:54:02.599 +little bit about that and also + +00:53:58.920 --> 00:54:06.079 +multilingual LP I'm going to have + +00:54:02.599 --> 00:54:09.119 +fure so also if you have any suggestions + +00:54:06.079 --> 00:54:11.400 +um we have two guest lecture slots still + +00:54:09.119 --> 00:54:12.799 +open uh that I'm trying to fill so if + +00:54:11.400 --> 00:54:15.440 +you have any things that you really want + +00:54:12.799 --> 00:54:16.440 +to hear about um I could either add them + +00:54:15.440 --> 00:54:19.319 +to the + +00:54:16.440 --> 00:54:21.079 +existing you know content or I could + +00:54:19.319 --> 00:54:23.240 +invite a guest lecturer who's working on + +00:54:21.079 --> 00:54:24.079 +that topic so you know please feel free + +00:54:23.240 --> 00:54:26.760 +to tell + +00:54:24.079 --> 00:54:29.160 +me um then the class format and + +00:54:26.760 --> 00:54:32.280 +structure uh the class + +00:54:29.160 --> 00:54:34.000 +content my goal is to learn in detail + +00:54:32.280 --> 00:54:36.640 +about building NLP systems from a + +00:54:34.000 --> 00:54:40.520 +research perspective so this is a 700 + +00:54:36.640 --> 00:54:43.599 +level course so it's aiming to be for + +00:54:40.520 --> 00:54:46.960 +people who really want to try new and + +00:54:43.599 --> 00:54:49.280 +Innovative things in uh kind of natural + +00:54:46.960 --> 00:54:51.359 +language processing it's not going to + +00:54:49.280 --> 00:54:52.760 +focus solely on reimplementing things + +00:54:51.359 --> 00:54:54.319 +that have been done before including in + +00:54:52.760 --> 00:54:55.280 +the project I'm going to be expecting + +00:54:54.319 --> 00:54:58.480 +everybody to do something something + +00:54:55.280 --> 00:54:59.920 +that's kind of new whether it's coming + +00:54:58.480 --> 00:55:01.359 +up with a new method or applying + +00:54:59.920 --> 00:55:03.559 +existing methods to a place where they + +00:55:01.359 --> 00:55:05.079 +haven't been used before or building out + +00:55:03.559 --> 00:55:06.640 +things for a new language or something + +00:55:05.079 --> 00:55:08.359 +like that so that's kind of one of the + +00:55:06.640 --> 00:55:11.480 +major goals of this + +00:55:08.359 --> 00:55:13.000 +class um learn basic and advanced topics + +00:55:11.480 --> 00:55:15.559 +in machine learning approaches to NLP + +00:55:13.000 --> 00:55:18.359 +and language models learn some basic + +00:55:15.559 --> 00:55:21.480 +linguistic knowledge useful in NLP uh + +00:55:18.359 --> 00:55:23.200 +see case studies of NLP applications and + +00:55:21.480 --> 00:55:25.680 +learn how to identify unique problems + +00:55:23.200 --> 00:55:29.039 +for each um one thing i' like to point + +00:55:25.680 --> 00:55:31.160 +out is I'm not going to cover every NLP + +00:55:29.039 --> 00:55:32.920 +application ever because that would be + +00:55:31.160 --> 00:55:35.520 +absolutely impossible NLP is being used + +00:55:32.920 --> 00:55:37.079 +in so many different areas nowadays but + +00:55:35.520 --> 00:55:38.960 +what I want people to pay attention to + +00:55:37.079 --> 00:55:41.280 +like even if you're not super interested + +00:55:38.960 --> 00:55:42.400 +in code generation for example what you + +00:55:41.280 --> 00:55:44.200 +can do is you can look at code + +00:55:42.400 --> 00:55:46.160 +generation look at how people identify + +00:55:44.200 --> 00:55:47.680 +problems look at the methods that people + +00:55:46.160 --> 00:55:50.880 +have proposed to solve those unique + +00:55:47.680 --> 00:55:53.039 +problems and then kind of map that try + +00:55:50.880 --> 00:55:54.799 +to do some generalization onto your own + +00:55:53.039 --> 00:55:57.799 +problems of Interest so uh that's kind + +00:55:54.799 --> 00:56:00.280 +of the goal of the NLP + +00:55:57.799 --> 00:56:02.440 +applications finally uh learning how to + +00:56:00.280 --> 00:56:05.160 +debug when and where NLP systems fail + +00:56:02.440 --> 00:56:08.200 +and build improvements based on this so + +00:56:05.160 --> 00:56:10.200 +um ever since I was a graduate student + +00:56:08.200 --> 00:56:12.720 +this has been like one of the really + +00:56:10.200 --> 00:56:15.920 +important things that I feel like I've + +00:56:12.720 --> 00:56:17.440 +done well or done better than some other + +00:56:15.920 --> 00:56:19.280 +people and I I feel like it's a really + +00:56:17.440 --> 00:56:21.119 +good way to like even if you're only + +00:56:19.280 --> 00:56:22.680 +interested in improving accuracy knowing + +00:56:21.119 --> 00:56:25.039 +why your system's failing still is the + +00:56:22.680 --> 00:56:27.599 +best way to do that I so I'm going to + +00:56:25.039 --> 00:56:30.559 +put a lot of emphasis on + +00:56:27.599 --> 00:56:32.559 +that in terms of the class format um + +00:56:30.559 --> 00:56:36.280 +before class for some classes there are + +00:56:32.559 --> 00:56:37.880 +recommended reading uh this can be + +00:56:36.280 --> 00:56:39.559 +helpful to read I'm never going to + +00:56:37.880 --> 00:56:41.119 +expect you to definitely have read it + +00:56:39.559 --> 00:56:42.480 +before the class but I would suggest + +00:56:41.119 --> 00:56:45.160 +that maybe you'll get more out of the + +00:56:42.480 --> 00:56:47.319 +class if you do that um during class + +00:56:45.160 --> 00:56:48.079 +we'll have the lecture um in discussion + +00:56:47.319 --> 00:56:50.559 +with + +00:56:48.079 --> 00:56:52.359 +everybody um sometimes we'll have a code + +00:56:50.559 --> 00:56:55.839 +or data walk + +00:56:52.359 --> 00:56:58.760 +um actually this is a a little bit old I + +00:56:55.839 --> 00:57:01.880 +I have this slide we're this year we're + +00:56:58.760 --> 00:57:04.160 +going to be adding more uh code and data + +00:57:01.880 --> 00:57:07.400 +walks during office hours and the way it + +00:57:04.160 --> 00:57:09.400 +will work is one of the Tas we have + +00:57:07.400 --> 00:57:11.160 +seven Tas who I'm going to introduce + +00:57:09.400 --> 00:57:15.000 +very soon but one of the Tas will be + +00:57:11.160 --> 00:57:16.839 +doing this kind of recitation where you + +00:57:15.000 --> 00:57:18.200 +um where we go over a library so if + +00:57:16.839 --> 00:57:19.480 +you're not familiar with the library and + +00:57:18.200 --> 00:57:21.960 +you want to be more familiar with the + +00:57:19.480 --> 00:57:23.720 +library you can join this and uh then + +00:57:21.960 --> 00:57:25.400 +we'll be able to do this and this will + +00:57:23.720 --> 00:57:28.240 +cover things like + +00:57:25.400 --> 00:57:31.039 +um pie torch and sentence piece uh we're + +00:57:28.240 --> 00:57:33.280 +going to start out with hugging face um + +00:57:31.039 --> 00:57:36.559 +inference stuff like + +00:57:33.280 --> 00:57:41.520 +VM uh debugging software like + +00:57:36.559 --> 00:57:41.520 +Xeno um what were the other + +00:57:41.960 --> 00:57:47.200 +ones oh the open AI API and light llm + +00:57:45.680 --> 00:57:50.520 +other stuff like that so we we have lots + +00:57:47.200 --> 00:57:53.599 +of them planned we'll uh uh we'll update + +00:57:50.520 --> 00:57:54.839 +that um and then after class after + +00:57:53.599 --> 00:57:58.079 +almost every class we'll have a question + +00:57:54.839 --> 00:58:00.079 +quiz um and the quiz is intended to just + +00:57:58.079 --> 00:58:02.000 +you know make sure that you uh paid + +00:58:00.079 --> 00:58:04.480 +attention to the material and are able + +00:58:02.000 --> 00:58:07.520 +to answer questions about it we will aim + +00:58:04.480 --> 00:58:09.559 +to release it on the day of the course + +00:58:07.520 --> 00:58:11.599 +the day of the actual lecture and it + +00:58:09.559 --> 00:58:14.559 +will be due at the end of the following + +00:58:11.599 --> 00:58:15.960 +day of the lecture so um it will be + +00:58:14.559 --> 00:58:18.920 +three questions it probably shouldn't + +00:58:15.960 --> 00:58:20.680 +take a whole lot of time but um uh yeah + +00:58:18.920 --> 00:58:23.400 +so we'll H + +00:58:20.680 --> 00:58:26.319 +that in terms of assignments assignment + +00:58:23.400 --> 00:58:28.640 +one is going to be build your own llama + +00:58:26.319 --> 00:58:30.200 +and so what this is going to look like + +00:58:28.640 --> 00:58:32.680 +is we're going to give you a partial + +00:58:30.200 --> 00:58:34.319 +implementation of llama which is kind of + +00:58:32.680 --> 00:58:37.960 +the most popular open source language + +00:58:34.319 --> 00:58:40.160 +model nowadays and ask you to fill in um + +00:58:37.960 --> 00:58:42.839 +ask you to fill in the parts we're going + +00:58:40.160 --> 00:58:45.920 +to train a very small version of llama + +00:58:42.839 --> 00:58:47.319 +on a small data set and get it to work + +00:58:45.920 --> 00:58:48.880 +and the reason why it's very small is + +00:58:47.319 --> 00:58:50.480 +because the smallest actual version of + +00:58:48.880 --> 00:58:53.039 +llama is 7 billion + +00:58:50.480 --> 00:58:55.359 +parameters um and that might be a little + +00:58:53.039 --> 00:58:58.400 +bit difficult to train with + +00:58:55.359 --> 00:59:00.680 +resources um for assignment two we're + +00:58:58.400 --> 00:59:04.559 +going to try to do an NLP task from + +00:59:00.680 --> 00:59:06.920 +scratch and so the way this will work is + +00:59:04.559 --> 00:59:08.520 +we're going to give you an assignment + +00:59:06.920 --> 00:59:10.880 +which we're not going to give you an + +00:59:08.520 --> 00:59:13.400 +actual data set and instead we're going + +00:59:10.880 --> 00:59:15.760 +to ask you to uh perform data creation + +00:59:13.400 --> 00:59:19.359 +modeling and evaluation for a specified + +00:59:15.760 --> 00:59:20.640 +task and so we're going to tell you uh + +00:59:19.359 --> 00:59:22.599 +what to do but we're not going to tell + +00:59:20.640 --> 00:59:26.400 +you exactly how to do it but we're going + +00:59:22.599 --> 00:59:29.680 +to try to give as conrete directions as + +00:59:26.400 --> 00:59:32.359 +we can um + +00:59:29.680 --> 00:59:34.160 +yeah will you be given a parameter limit + +00:59:32.359 --> 00:59:36.559 +on the model so that's a good question + +00:59:34.160 --> 00:59:39.119 +or like a expense limit or something + +00:59:36.559 --> 00:59:40.440 +like that um I maybe actually I should + +00:59:39.119 --> 00:59:44.240 +take a break from the assignments and + +00:59:40.440 --> 00:59:46.520 +talk about compute so right now um for + +00:59:44.240 --> 00:59:49.319 +assignment one we're planning on having + +00:59:46.520 --> 00:59:51.599 +this be able to be done either on a Mac + +00:59:49.319 --> 00:59:53.520 +laptop with an M1 or M2 processor which + +00:59:51.599 --> 00:59:57.079 +I think a lot of people have or Google + +00:59:53.520 --> 00:59:59.839 +collab um so it should be like + +00:59:57.079 --> 01:00:02.160 +sufficient to use free computational + +00:59:59.839 --> 01:00:03.640 +resources that you have for number two + +01:00:02.160 --> 01:00:06.079 +we'll think about that I think that's + +01:00:03.640 --> 01:00:08.280 +important we do have Google cloud + +01:00:06.079 --> 01:00:11.520 +credits for $50 for everybody and I'm + +01:00:08.280 --> 01:00:13.440 +working to get AWS credits for more um + +01:00:11.520 --> 01:00:18.160 +but the cloud providers nowadays are + +01:00:13.440 --> 01:00:19.680 +being very stingy so um so it's uh been + +01:00:18.160 --> 01:00:22.160 +a little bit of a fight to get uh + +01:00:19.680 --> 01:00:23.680 +credits but I I it is very important so + +01:00:22.160 --> 01:00:28.480 +I'm going to try to get as as many as we + +01:00:23.680 --> 01:00:31.119 +can um and so yeah I I think basically + +01:00:28.480 --> 01:00:32.280 +uh there will be some sort of like limit + +01:00:31.119 --> 01:00:34.480 +on the amount of things you can + +01:00:32.280 --> 01:00:36.240 +practically do and so because of that + +01:00:34.480 --> 01:00:39.920 +I'm hoping that people will rely very + +01:00:36.240 --> 01:00:43.359 +heavily on pre-trained models um or uh + +01:00:39.920 --> 01:00:46.079 +yeah pre-trained models + +01:00:43.359 --> 01:00:49.599 +and yeah so that that's the the short + +01:00:46.079 --> 01:00:52.799 +story B um the second thing uh the + +01:00:49.599 --> 01:00:54.720 +assignment three is to do a survey of + +01:00:52.799 --> 01:00:57.920 +some sort of state-ofthe-art research + +01:00:54.720 --> 01:01:00.760 +resarch and do a reimplementation of + +01:00:57.920 --> 01:01:02.000 +this and in doing this again you will + +01:01:00.760 --> 01:01:03.440 +have to think about something that's + +01:01:02.000 --> 01:01:06.359 +feasible within computational + +01:01:03.440 --> 01:01:08.680 +constraints um and so you can discuss + +01:01:06.359 --> 01:01:11.839 +with your Tas about uh about the best + +01:01:08.680 --> 01:01:13.920 +way to do this um and then the final + +01:01:11.839 --> 01:01:15.400 +project is to perform a unique project + +01:01:13.920 --> 01:01:17.559 +that either improves on the state-of-the + +01:01:15.400 --> 01:01:21.000 +art with respect to whatever you would + +01:01:17.559 --> 01:01:23.440 +like to improve with this could be uh + +01:01:21.000 --> 01:01:25.280 +accuracy for sure this could be + +01:01:23.440 --> 01:01:27.760 +efficiency + +01:01:25.280 --> 01:01:29.599 +it could be some sense of + +01:01:27.760 --> 01:01:31.520 +interpretability but if it's going to be + +01:01:29.599 --> 01:01:33.599 +something like interpretability you'll + +01:01:31.520 --> 01:01:35.440 +have to discuss with us what that means + +01:01:33.599 --> 01:01:37.240 +like how we measure that how we can like + +01:01:35.440 --> 01:01:40.839 +actually say that you did a good job + +01:01:37.240 --> 01:01:42.839 +with improving that um another thing + +01:01:40.839 --> 01:01:44.680 +that you can do is take whatever you + +01:01:42.839 --> 01:01:47.280 +implemented for assignment 3 and apply + +01:01:44.680 --> 01:01:49.039 +it to a new task or apply it to a new + +01:01:47.280 --> 01:01:50.760 +language that has never been examined + +01:01:49.039 --> 01:01:53.119 +before so these are also acceptable + +01:01:50.760 --> 01:01:54.240 +final projects but basically the idea is + +01:01:53.119 --> 01:01:55.559 +for the final project you need to do + +01:01:54.240 --> 01:01:57.480 +something something new that hasn't been + +01:01:55.559 --> 01:01:59.880 +done before and create new knowledge + +01:01:57.480 --> 01:02:04.520 +with the respect + +01:01:59.880 --> 01:02:07.640 +toy um so for this the instructor is me + +01:02:04.520 --> 01:02:09.920 +um I'm uh looking forward to you know + +01:02:07.640 --> 01:02:13.599 +discussing and working with all of you + +01:02:09.920 --> 01:02:16.119 +um for TAS we have seven Tas uh two of + +01:02:13.599 --> 01:02:18.319 +them are in transit so they're not here + +01:02:16.119 --> 01:02:22.279 +today um the other ones uh Tas would you + +01:02:18.319 --> 01:02:22.279 +mind coming up uh to introduce + +01:02:23.359 --> 01:02:26.359 +yourself + +01:02:28.400 --> 01:02:32.839 +so um yeah nhir and akshai couldn't be + +01:02:31.599 --> 01:02:34.039 +here today because they're traveling + +01:02:32.839 --> 01:02:37.119 +I'll introduce them later because + +01:02:34.039 --> 01:02:37.119 +they're coming uh next + +01:02:40.359 --> 01:02:46.480 +time cool and what I'd like everybody to + +01:02:43.000 --> 01:02:48.680 +do is say um like you know what your + +01:02:46.480 --> 01:02:53.079 +name is uh what + +01:02:48.680 --> 01:02:55.799 +your like maybe what you're interested + +01:02:53.079 --> 01:02:57.319 +in um and the reason the goal of this is + +01:02:55.799 --> 01:02:59.200 +number one for everybody to know who you + +01:02:57.319 --> 01:03:00.720 +are and number two for everybody to know + +01:02:59.200 --> 01:03:03.440 +who the best person to talk to is if + +01:03:00.720 --> 01:03:03.440 +they're interested in + +01:03:04.200 --> 01:03:09.079 +particular hi uh I'm + +01:03:07.000 --> 01:03:15.520 +Aila second + +01:03:09.079 --> 01:03:15.520 +year I work on language and social + +01:03:16.200 --> 01:03:24.559 +and I'm I'm a second this year PhD + +01:03:21.160 --> 01:03:26.799 +student Grand and Shar with you I search + +01:03:24.559 --> 01:03:28.480 +is like started in the border of MP and + +01:03:26.799 --> 01:03:31.000 +computer interaction with a lot of work + +01:03:28.480 --> 01:03:32.640 +on automating parts of the developer + +01:03:31.000 --> 01:03:35.319 +experience to make it easier for anyone + +01:03:32.640 --> 01:03:35.319 +to + +01:03:39.090 --> 01:03:42.179 +[Music] + +01:03:47.520 --> 01:03:53.279 +orif + +01:03:50.079 --> 01:03:54.680 +everyone first + +01:03:53.279 --> 01:03:57.119 +year + +01:03:54.680 --> 01:04:00.119 +[Music] + +01:03:57.119 --> 01:04:03.559 +I don't like updating primar models I + +01:04:00.119 --> 01:04:03.559 +hope to not update Prim + +01:04:14.599 --> 01:04:19.400 +modelm yeah thanks a lot everyone and + +01:04:17.200 --> 01:04:19.400 +yeah + +01:04:20.839 --> 01:04:29.400 +than and so we will um we'll have people + +01:04:25.640 --> 01:04:30.799 +uh kind of have office hours uh every ta + +01:04:29.400 --> 01:04:32.880 +has office hours at a regular time + +01:04:30.799 --> 01:04:34.480 +during the week uh please feel free to + +01:04:32.880 --> 01:04:38.400 +come to their office hours or my office + +01:04:34.480 --> 01:04:41.960 +hours um I think they are visha are they + +01:04:38.400 --> 01:04:43.880 +posted on the site or okay yeah they + +01:04:41.960 --> 01:04:47.240 +they either are or will be posted on the + +01:04:43.880 --> 01:04:49.720 +site very soon um and come by to talk + +01:04:47.240 --> 01:04:51.480 +about anything uh if there's nobody in + +01:04:49.720 --> 01:04:53.079 +my office hours I'm happy to talk about + +01:04:51.480 --> 01:04:54.599 +things that are unrelated but if there's + +01:04:53.079 --> 01:04:58.039 +lots of people waiting outside or I + +01:04:54.599 --> 01:05:00.319 +might limit it to uh like um just things + +01:04:58.039 --> 01:05:02.480 +about the class so cool and we have + +01:05:00.319 --> 01:05:04.760 +Patza we'll be checking that regularly + +01:05:02.480 --> 01:05:06.839 +uh striving to get you an answer in 24 + +01:05:04.760 --> 01:05:12.240 +hours on weekdays over weekends we might + +01:05:06.839 --> 01:05:16.000 +not so um yeah so that's all for today + +01:05:12.240 --> 01:05:16.000 +are there any questions