Implement the ARC Challenge evaluation

From the GPT-3 paper

ARC [CCE+18] is a dataset of multiple-choice questions collected from 3rd to 9th grade science exams. On the “Challenge” version of the dataset which has been filtered to questions which simple statistical or information retrieval methods are unable to correctly answer, GPT-3 achieves 51.4% accuracy in the zero-shot setting, 53.2% in the one-shot setting, and 51.5% in the few-shot setting. This is approaching the performance of a fine-tuned RoBERTa baseline (55.9%) from UnifiedQA [KKS+20]. On the “Easy” version of the dataset (questions which either of the mentioned baseline approaches answered correctly), GPT-3 achieves 68.8%, 71.2%, and 70.1% which slightly exceeds a fine-tuned RoBERTa baseline from [KKS+20]. However, both of these results are still much worse than the overall SOTAs achieved by the UnifiedQA which exceeds GPT-3’s few-shot results by 27% on the challenge set and 22% on the easy set.

[X] Data processing code implemented
[x] Evaluation implemented

The evaluation code should be modeled after the interface in lm_eval/base.py and the example of the BoolQ task in lm_eval/tasks/suerglue.py

EleutherAI / lm-evaluation-harness

Implement the ARC Challenge evaluation #15