Add evaluation results on the plain_text config of squad

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

@lewtun

, using the predictions stored [here](https://huggingface.co/datasets/autoevaluate/autoeval-staging-eval-project-976d13e6-0b05-475e-9b4e-e8fbc174cfae-346).\
Accept this pull request to see the results displayed on the [Hub leaderboard](https://huggingface.co/spaces/autoevaluate/leaderboards?dataset=squad).\
Evaluate your model on more datasets [here](https://huggingface.co/spaces/autoevaluate/model-evaluator?dataset=squad).

README.md

@@ -6,7 +6,28 @@ datasets:
 - squad
 model-index:
 - name: extractive-question-answering
-  results: []
+  results:
+  - task:
+      type: question-answering
+      name: Question Answering
+    dataset:
+      name: squad
+      type: squad
+      config: plain_text
+      split: validation
+    metrics:
+    - name: Loss
+      type: loss
+      value: 1.2488619089126587
+      verified: true
+    - name: exact_match
+      type: exact_match
+      value: 72.5436
+      verified: true
+    - name: f1
+      type: f1
+      value: 81.8688
+      verified: true
 ---
 
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