Add evaluation results on the default config of xsum

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Your model has been evaluated on the default config of the [xsum](https://huggingface.co/datasets/xsum) dataset by

@sysresearch101
, using the predictions stored [here](https://huggingface.co/datasets/autoevaluate/autoeval-staging-eval-project-xsum-d7ddcd7b-12845708).\
Accept this pull request to see the results displayed on the [Hub leaderboard](https://huggingface.co/spaces/autoevaluate/leaderboards?dataset=xsum).\
Evaluate your model on more datasets [here](https://huggingface.co/spaces/autoevaluate/model-evaluator?dataset=xsum).

README.md

@@ -13,8 +13,8 @@ model-index:
       type: summarization
       name: Summarization
     dataset:
-      name: xsum 
-      type: xsum 
+      name: xsum
+      type: xsum
       config: 3.0.0
       split: train
     metrics:
@@ -42,6 +42,39 @@ model-index:
       type: gen_len
       value: <TODO>
       verified: true
+  - task:
+      type: summarization
+      name: Summarization
+    dataset:
+      name: xsum
+      type: xsum
+      config: default
+      split: test
+    metrics:
+    - name: ROUGE-1
+      type: rouge
+      value: 26.8921
+      verified: true
+    - name: ROUGE-2
+      type: rouge
+      value: 6.9411
+      verified: true
+    - name: ROUGE-L
+      type: rouge
+      value: 21.2832
+      verified: true
+    - name: ROUGE-LSUM
+      type: rouge
+      value: 21.284
+      verified: true
+    - name: loss
+      type: loss
+      value: 2.5411810874938965
+      verified: true
+    - name: gen_len
+      type: gen_len
+      value: 18.7755
+      verified: true
 ---
 
 # T5-large Summarization Model Trained on the XSUM Dataset