9. The system of claim 8 , wherein generating a score indicative of the probability that the transcription of the voice query is correct comprises: generating scores based on multiple different types of user actions indicated by feedback information, each of the multiple different types of user actions being taken by a respective user that submitted the voice query.
8. A system comprising: one or more computers and one or more storage devices storing instructions that are operable, when executed by the one or more computers, to cause the one or more computers to perform operations comprising: receiving a particular voice query submitted by a user; receiving feedback information from a user after the user is presented with a set of search results that was generated in response to a search query that included a transcription of the particular voice query; generating a score indicative of a probability that the transcription of the voice query is correct based at least on the feedback information; determining that the score that is generated based at least on the feedback information satisfies a threshold; and in response to determining that the score that is generated based at least on the feedback information satisfies the threshold, adapting an acoustic model using the particular voice query.