Natixis Global Asset Management will acquire AlphaSimplex Group, the investment management firm founded and run by Massachusetts Institute of Technology professor and behavioral finance pioneer Andrew W. Lo, said spokesman Raymond J. ORourke. Terms werent disclosed. In a news release, Jeremiah Chafkin, president of Natixis alternatives group, cited Mr. Los pioneering work in alternative beta replication as an area of great interest for institutional investors. In an interview, Mr. Lo said the strategic relationship with Natixis will allow AlphaSimplex, which has quietly grown to $500 million in assets under management since 1999 with no marketing or distribution staff, to implement a number of investment ideas on as broad a platform as possible. Mr. Lo will remain chairman and chief scientific officer of AlphaSimplex.