What to Expect from Expected Kneser-Ney Smoothing

Kneser-Ney smoothing on expected counts was proposed recently in Zhang et al. 2014. In this paper we revisit this technique and suggest a number of optimizations and extensions. We then analyze its performance in several practical speech recognition scenarios that depend on fractional sample counts, such as training on uncertain data, language model adaptation and Word-Phrase-Entity models. We show that the proposed approach to smoothing outperforms known alternatives by a significant margin.