Ben Horowitz — Education: B.A. Computer Science, Columbia University; M.S. Computer Science, UCLA

NoteThe source text directly confirms all elements of the claim: (1) B.A. from Columbia University in computer science, (2) M.S. from UCLA in computer science. The degrees, institutions, and fields of study all match exactly. The source also confirms the infobox listing 'Columbia University (BA)' and 'University of California, Los Angeles (MS)'.