The new end-to-end speech recognition approach (Graves et al., 2006;Graves and Jaitly, 2014;Hannun et al., 2014;Miao et al., 2015;Chorowski et al., 2015;Chan et al., 2016; integrates all available information within a single neural network model, allows to make fusing conversational-context information possible.
these are limited to encode only one preceding utterance and learn from a few hundred hours of annotated speech corpus, leading to minimal improvements.