US Patent 9292487 Discriminative language model pruning

A language model for speech recognition may be discriminatively pruned. In some embodiments, the language model is discriminatively pruned by computing a discriminative objective function value for one or more n-grams in the language model, and selecting one or more n-grams to prune based at least in part on a threshold value. In some embodiments, the language model is discriminatively pruned to a sufficiently small number of n-grams such that transcription of audio inputs may occur in real time, or such that the pruned language model may be stored on a device with relatively limited electronic storage capacity.