Recently, the RNN-based generators have shown improving results in tackling the NLG problems in task oriented-dialogue systems with varied proposed methods, such as HLSTM (Wen et al., 2015a), SCLSTM (Wen et al., 2015b), or espe-cially RNN Encoder-Decoder models integrating with attention mechanism, such as Enc-Dec (Wen et al., 2016b), and RALSTM .
such models have proved to work well only when providing a sufficient in-domain data since a modest dataset may harm the models' performance.