CIAL at the NTCIR-13 STC-2 Task

Short text conversation (STC) has emerged as a prominent research topic and gained considerable attention in recent years. While it is still an open problem whether the retrievalbased method should be replaced by or combined with generative models for STC task, the NTCIR-13 STC-2 Task provides a transparent platform to compare the two aforementioned methods via doing comprehensive evaluations. In this task, we proposed a retrieval-based method with distributed vector representation, and a generation-based method with recurrent neural networks. Overall, we submitted 4 and 1 official runs for retrieval and generation settings, respectively. We also proposed a data augmentation method for extending the amount of labeled data that is more sufficient for training a generative model.