18. One or more computer-readable storage media storing computer-executable instructions that, when executed on one or more processors, causes the one or more processors to perform acts comprising: retrieving a number (N) of electronic documents; representing each retrieved document as a respective vector of a term-document matrix D; defining a first equation having terms including the term-document matrix D, a term-topic matrix U, a topic-document matrix V, the term-topic matrix U and the topic-document matrix V are related such that a matrix multiplication of the term-topic matrix U and the topic-document matrix V is approximated as the term-document matrix D; independently solving in parallel for vectors of the topic-document matrix V and the term-topic matrix U; and updating the topic-document matrix V and the term-topic matrix U based at least in part of the solved vectors of the document matrix V and the term-topic matrix U; and storing at least one of the document matrix V and the term-topic matrix U.
18. One or more computer-readable storage media storing computer-executable instructions that, when executed on one or more processors, causes the one or more processors to perform acts comprising: retrieving a number (N) of electronic documents; representing each retrieved document as a respective vector of a term-document matrix D; defining a first equation having terms including the term-document matrix D, a term-topic matrix U, a topic-document matrix V, the term-topic matrix U and the topic-document matrix V are related such that a matrix multiplication of the term-topic matrix U and the topic-document matrix V is approximated as the term-document matrix D; independently solving in parallel for vectors of the topic-document matrix V and the term-topic matrix U; and updating the topic-document matrix V and the term-topic matrix U based at least in part of the solved vectors of the document matrix V and the term-topic matrix U; and storing at least one of the document matrix V and the term-topic matrix U. 20. The one or more computer-readable storage media as recited in claim 18 , wherein the independently solving in parallel for vectors of the topic-document matrix V and the term-topic matrix U comprises: holding the topic-document matrix V fixed while solving in parallel for the vectors of the term-topic matrix U; and holding the term-topic matrix U fixed while solving in parallel for the vectors of the topic-document matrix V.