Before revision:  Specifically, we first build a weighted bidirectional graph based on clinical dialogues to depict the relationship between symptoms and diseases and then present a bidirectional graph based deep Q-network ( BG-DQN ) for dialogue management.
After revision:  Specifically, we first build a weighted bidirectional graph based on symptom co-occurrence and a proposed symptom frequency-inverse disease frequency. Then this work proposes a graph based deep Q-network ( BG-DQN ) for dialogue management.