9. One or more computer storage media having computer-executable instructions embodied thereon that, when executed by a computing system having a processor and memory, cause the computing system to personalize a language model for a particular target user, the computer-executable instructions causing the computing system to: identify a first set of data from usage history associated with the target user, the first set of data comprising at least one entity or user action; analyzing the usage history information for statistical data; map the first set of data to a personalized knowledge source for the target user, wherein the mapping comprises assigning probabilities to entities and relationships in the personalized knowledge source based on the statistical data, thereby providing a probabilistic personalized knowledge source; determine a set of users similar to the target user; map a second set of data to the personalized knowledge source for the target user, the second set of data comprising at least one entity or user action corresponding to the set of users similar to the target user, thereby creating an extended personalized knowledge source, the extended personalized knowledge source comprising a second entity and a triple indicating a relationship between the at least one entity or user action and the second entity, the mapping comprising at least one of incrementing a count of the one or more of the entity or calculating a weight of the one or more of the entity; and utilize the extended personalized knowledge source to build a personal language model for the target user for speech recognition.
9. One or more computer storage media having computer-executable instructions embodied thereon that, when executed by a computing system having a processor and memory, cause the computing system to personalize a language model for a particular target user, the computer-executable instructions causing the computing system to: identify a first set of data from usage history associated with the target user, the first set of data comprising at least one entity or user action; analyzing the usage history information for statistical data; map the first set of data to a personalized knowledge source for the target user, wherein the mapping comprises assigning probabilities to entities and relationships in the personalized knowledge source based on the statistical data, thereby providing a probabilistic personalized knowledge source; determine a set of users similar to the target user; map a second set of data to the personalized knowledge source for the target user, the second set of data comprising at least one entity or user action corresponding to the set of users similar to the target user, thereby creating an extended personalized knowledge source, the extended personalized knowledge source comprising a second entity and a triple indicating a relationship between the at least one entity or user action and the second entity, the mapping comprising at least one of incrementing a count of the one or more of the entity or calculating a weight of the one or more of the entity; and utilize the extended personalized knowledge source to build a personal language model for the target user for speech recognition. 15. The one or more computer storage media of claim 9 , wherein the personalized knowledge source includes one or more entities and entity relations, and further comprising weighting the one or more entities and entity relations based on a number of times that the entities and entity relations occur in the first set of data.