The CVAE based models incorporate stochastic latent variables into decoders in order to generate more relevant and diverse responses (Serban et al., 2017;Shen et al., 2017).
existing CVAE * Corresponding author based models normally rely on the unimodal distribution with a single latent variable to provide the global guidance to response generation, which is not sufficient to capture the complex semantics and high variability of responses.