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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi, <o:p></o:p></p><p class=MsoNormal>Could you please elaborate why ICA is reference-free? In other words, does different kinds of referencing methods (avg-ref or …) effect on ICA maps and source series ? <o:p></o:p></p><p class=MsoNormal>Suppose: x(t) is the signal then we have s(t)=M(^-1). x(t) ;where s(t) is source signals and M is the mixing matrix.<o:p></o:p></p><p class=MsoNormal>Now how come for y=x(t)-r(t) - where r(t) is another reference- result same/different maps and source series would be obtained and how could someone get the same dipole locations with different re-referencing methods?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>It would be great if someone gives in depth <b>methodological and mathematical explanations</b> rather than just qualitative explanations.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best<o:p></o:p></p><p class=MsoNormal>Iman<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b>-------------------------------------------------------------<o:p></o:p></b></p><p class=MsoNormal><b>Iman M.Rezazadeh, Ph.D<o:p></o:p></b></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Research Fellow<o:p></o:p></p><p class=MsoNormal>Semel Intitute, UCLA , Los Angeles<o:p></o:p></p><p class=MsoNormal>& Center for Mind and Brain, UC DAVIS, Davis<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>