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

@lewtun

, using the predictions stored [here](https://huggingface.co/datasets/autoevaluate/autoeval-staging-eval-project-xsum-c7d88063-10885461).\
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

@@ -209,6 +209,39 @@ model-index:
       type: gen_len
       value: 34.464
       verified: true
+  - task:
+      type: summarization
+      name: Summarization
+    dataset:
+      name: xsum
+      type: xsum
+      config: default
+      split: test
+    metrics:
+    - name: ROUGE-1
+      type: rouge
+      value: 20.5398
+      verified: true
+    - name: ROUGE-2
+      type: rouge
+      value: 3.4827
+      verified: true
+    - name: ROUGE-L
+      type: rouge
+      value: 13.647
+      verified: true
+    - name: ROUGE-LSUM
+      type: rouge
+      value: 15.8818
+      verified: true
+    - name: loss
+      type: loss
+      value: .nan
+      verified: true
+    - name: gen_len
+      type: gen_len
+      value: 81.4964
+      verified: true
 ---
 
 # long-t5-tglobal-base-16384 + BookSum