<span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">Hi Andrea,</span><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">
<br></div><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">Are you referring to pre-whitening by removing the first parameter of an auto-regressive model, thereby removing most (if not all) of the 1/f shape in the spectrum? If so, this can be done by taking the first temporal derivative of the raw-data, effectively setting the first AR parameter to 0. This is implemented by setting cfg.derivative = 'yes' in preprocessing. </div>
<div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">I don't know of any good references for this trick though, so if anybody else can help out, that'd be great.</div>
<div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)"><br></div><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">
Best,<br>Roemer</div><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)"><br></div><br><div class="gmail_quote">On Fri, Sep 14, 2012 at 12:27 PM, andrea brovelli <span dir="ltr"><<a href="mailto:andrea.brovelli@univ-amu.fr" target="_blank">andrea.brovelli@univ-amu.fr</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Dear all,<br>
<br>
I was wondering whether we can whiten the data using the cfg options in the ft_preprocessing function. Does anyone know ?<br>
<br>
Or does anyone have some code for prewhitening raw data ?<br>
<br>
Thanks a lot<br>
<br>
Andrea<br>
<br>
<br>
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</blockquote></div><br><br clear="all"><div><br></div>-- <br><font size="3"><font color="darkblue"><font face="calibri">Roemer
van der Meij M.Sc.<br>
PhD student<br>
Donders Institute for Brain, Cognition and Behaviour<br>
Centre for Cognition<br>
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6500 HE Nijmegen<br>
The Netherlands<br>
Tel: +31(0)24 3655932<br>
E-mail: <a href="mailto:r.vandermeij@donders.ru.nl" target="_blank">r.vandermeij@donders.ru.nl</a></font></font></font><div style="padding:0px;margin-left:0px;margin-top:0px;overflow:hidden;word-wrap:break-word;color:black;font-size:10px;text-align:left;line-height:130%">
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