Task: Question Answering
Input (English): We adopt several standard metrics widely used in existing works to measure the performance of dialogue generation models, including BLEU BIBREF24, embedding-based metrics (Average, Extrema, Greedy and Coherence) BIBREF25, BIBREF26, entropy-based metrics (Ent-{1,2}) BIBREF0 and distinct metrics (Dist-{1,2,3} and Intra-{1,2,3}) BIBREF1, BIBREF6. 
 Question: What automatic evaluation metrics are used?
Output (English): BLEU embedding-based metrics (Average, Extrema, Greedy and Coherence) , entropy-based metrics (Ent-{1,2}) distinct metrics (Dist-{1,2,3} and Intra-{1,2,3})