empirical analysis of indirect network effects in the market for personal digital assistants harikesh nair1 assistant professor marketing graduate school business stanford university 518 memorial way ca 94305 email nair edu phone 650 736 4256 fax 725 9932 pradeep chintagunta robert law chicago 1101 east 58th street il 60637 e mail gsb uchicago 773 702 8015 0458 jean pierre dubé jdube 834 5377 may 14 2003 this version october 3 1 we thank editor associate and an anonymous referee detailed comments suggestions that significantly improved earlier draft paper r sukumar sima vasa chris bodmer npd group clarifications help with data jason wells handango com sharing us his insights on pda software industry also gunter hitsch puneet manchanda seminar participants at
