Add evaluation results on the squad_v2 config of squad_v2

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Your model has been evaluated on the squad_v2 config of the [squad_v2](https://huggingface.co/datasets/squad_v2) dataset by

@nbroad

, using the predictions stored [here](https://huggingface.co/datasets/autoevaluate/autoeval-eval-project-squad_v2-7b0e814c-1303349869).\
Accept this pull request to see the results displayed on the [Hub leaderboard](https://huggingface.co/spaces/autoevaluate/leaderboards?dataset=squad_v2).\
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README.md

@@ -9,7 +9,24 @@ datasets:
 - duorc
 model-index:
 - name: rob-base-superqa2
-  results: []
+  results:
+  - task:
+      type: question-answering
+      name: Question Answering
+    dataset:
+      name: squad_v2
+      type: squad_v2
+      config: squad_v2
+      split: validation
+    metrics:
+    - name: Exact Match
+      type: exact_match
+      value: 79.2365
+      verified: true
+    - name: F1
+      type: f1
+      value: 82.3326
+      verified: true
 ---
 
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