10. 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, by a speech-enabled home device of an automated speaker identification system that includes the speech-enabled home device that includes one or more microphones for detecting utterances spoken in a home environment, and a server based speaker recognition engine that is associated with an automated query processor and that includes (i) one or more text-dependent speaker identification models that are trained using multiple previous utterances of a keyword by a particular speaker and by other users whose accounts are registered with the server, and (ii) one or more text-independent speaker identification models that are trained using utterances of words other than the keyword by the particular speaker and by other users whose accounts are registered with the server, an audio signal encoding an utterance that was spoken in a home environment and was detected by one or more microphones of the speech-enabled home device, and that includes the keyword and a query; determining, by the server-based speaker recognition engine and based on an analysis of a portion of the audio signal that corresponds to the keyword by one or more of the text-dependent speaker identification models that are trained using utterances of the keyword by the particular speaker and by the other users whose accounts are registered with the server, a first speaker identification confidence value that reflects a likelihood that the particular speaker spoke the keyword; determining, by the server-based speaker recognition engine and based on an analysis of at least a portion of the audio signal that corresponds to the query by one or more of the text-independent speaker identification models that are trained using utterances of words other than the keyword by the particular speaker and by other users whose accounts are registered with the server, a second speaker identification confidence value that reflects a likelihood that the particular speaker spoke the query; determining, by the server-based speaker recognition engine, a first quantity of the utterances of the keyword by the particular speaker that were used to train the one or more text-dependent speaker identification models; determining, by the server-based speaker recognition engine, a second quantity of the utterances of the words other than the keyword by the particular speaker that were used to train the one or more text-independent speaker identification models; assigning, by the server-based speaker recognition engine, a first weight to the first speaker identification confidence value based at least on the first quantity of utterances of the keyword by the particular speaker that were used to train the one or more text-dependent speaker identification models, and a second weight to the second speaker identification confidence value based at least on the second quantity of utterances of the words other than the keyword by the particular speaker that were used to train the one or more text-independent speaker identification models; determining, by the server-based speaker recognition engine, that the particular speaker spoke the utterance encoded in the audio signal based at least in part on the weighted first speaker identification confidence value and the weighted second speaker identification confidence value; in response to determining by the server-based speaker recognition engine that the particular speaker spoke the utterance encoded in the audio signal based at least in part on the weighted first speaker identification confidence value and the weighted second speaker identification confidence value, initiating access to one or more account resources associated with the particular speaker for preparation of a personalized response to the query by the automated query processor that is associated with the server-based speaker recognition engine; and providing, by the automated query processor that is associated with the server-based speaker recognition engine, the personalized response to the speech-enabled home device for output to the particular speaker.
10. 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, by a speech-enabled home device of an automated speaker identification system that includes the speech-enabled home device that includes one or more microphones for detecting utterances spoken in a home environment, and a server based speaker recognition engine that is associated with an automated query processor and that includes (i) one or more text-dependent speaker identification models that are trained using multiple previous utterances of a keyword by a particular speaker and by other users whose accounts are registered with the server, and (ii) one or more text-independent speaker identification models that are trained using utterances of words other than the keyword by the particular speaker and by other users whose accounts are registered with the server, an audio signal encoding an utterance that was spoken in a home environment and was detected by one or more microphones of the speech-enabled home device, and that includes the keyword and a query; determining, by the server-based speaker recognition engine and based on an analysis of a portion of the audio signal that corresponds to the keyword by one or more of the text-dependent speaker identification models that are trained using utterances of the keyword by the particular speaker and by the other users whose accounts are registered with the server, a first speaker identification confidence value that reflects a likelihood that the particular speaker spoke the keyword; determining, by the server-based speaker recognition engine and based on an analysis of at least a portion of the audio signal that corresponds to the query by one or more of the text-independent speaker identification models that are trained using utterances of words other than the keyword by the particular speaker and by other users whose accounts are registered with the server, a second speaker identification confidence value that reflects a likelihood that the particular speaker spoke the query; determining, by the server-based speaker recognition engine, a first quantity of the utterances of the keyword by the particular speaker that were used to train the one or more text-dependent speaker identification models; determining, by the server-based speaker recognition engine, a second quantity of the utterances of the words other than the keyword by the particular speaker that were used to train the one or more text-independent speaker identification models; assigning, by the server-based speaker recognition engine, a first weight to the first speaker identification confidence value based at least on the first quantity of utterances of the keyword by the particular speaker that were used to train the one or more text-dependent speaker identification models, and a second weight to the second speaker identification confidence value based at least on the second quantity of utterances of the words other than the keyword by the particular speaker that were used to train the one or more text-independent speaker identification models; determining, by the server-based speaker recognition engine, that the particular speaker spoke the utterance encoded in the audio signal based at least in part on the weighted first speaker identification confidence value and the weighted second speaker identification confidence value; in response to determining by the server-based speaker recognition engine that the particular speaker spoke the utterance encoded in the audio signal based at least in part on the weighted first speaker identification confidence value and the weighted second speaker identification confidence value, initiating access to one or more account resources associated with the particular speaker for preparation of a personalized response to the query by the automated query processor that is associated with the server-based speaker recognition engine; and providing, by the automated query processor that is associated with the server-based speaker recognition engine, the personalized response to the speech-enabled home device for output to the particular speaker. 14. The system of claim 10 , wherein determining that the particular speaker spoke the utterance based at least on the weighted first speaker identification confidence value and the weighted second speaker identification confidence value comprises: combining the weighted first speaker identification confidence value and the weighted second speaker identification confidence value to generate a combined confidence; and determining that the combined confidence for the particular speaker is greater than a combined confidence for any other speaker.