22. The non-transitory computer readable medium of claim 19 , wherein the computer-executable module causes the computing device to generate the prediction performance model by generating a regression model based on the manually provided pronunciation for the words, the predicted pronunciation for the words, and a confidence score for the word.
19. A non-transitory computer readable medium storing a computer-executable module that, when executed by a processor of a computing device, cause the computing device to perform a process comprising: generating a prediction performance model for a pronunciation prediction model based on: a comparison of an automatically predicted pronunciation of a word with a manually provided pronunciation of the word, and confidence scores for the automatically predicted pronunciations, wherein the prediction performance model is adapted to generate performance information for a grapheme-to-phoneme model, the performance information indicating a degree of confidence in the grapheme-to-phoneme model to predict a new word added to a lexicon based upon an input predicted pronunciation generated by the grapheme-to-phoneme model for the new word and the confidence score for the input predicted pronunciation generated by the grapheme-to-phoneme model; generating, from the pronunciation prediction model, a pronunciation prediction for a candidate word to be added to the lexicon and a confidence score for the candidate word; generating, from the prediction performance model, an annotation priority for the candidate word based on the confidence score for the pronunciation prediction of the candidate word and the predicted pronunciation of the candidate word; generating a value identifying a relationship between the annotation priority for the candidate word and a threshold; and routing the candidate word to one of a manual pronunciation generator or an automatic pronunciation generator based on the value.