Synchronous Bidirectional Neural Machine Translation
Table 2: Experiment results on the development set using different fusion mechanism with different λs.
['Fusion Linear', 'Fusion Linear', '[ITALIC] λ =0.1 51.05', '[ITALIC] λ =0.5 50.71', '[ITALIC] λ =1.0 46.98']
Effect of Fusion Mechanism We first investigate the impact of different fusion mechanisms with different λs on the development set. Nonlinear interpolation, which is more robust than linear interpolation, achieves the best performance when we use tanh with λ=0.1. Compared to gate mechanism, nonlinear interpolation is much simpler and needs less parameters. Therefore, we will use nonlinear interpolation with tanh and λ=0.1 for all experiments thereafter.