<html><head><meta http-equiv="Content-Type" content="text/html charset=iso-8859-1"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Yes, it does removes the baseline from the data before computing ERPs and saving ERPs on disk (but this is only for ERP calculation in STUDY of course)<div><br></div><div>Arno</div><div><br><div><div>On Aug 29, 2014, at 8:23 AM, Angel Tabullo <<a href="mailto:angeltabullo@yahoo.com">angeltabullo@yahoo.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="font-family: Helvetica; font-size: 13px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div style="background-color: rgb(255, 255, 255); font-family: 'bookman old style', 'new york', times, serif; font-size: 14pt;"><div><span>Thanks for the reply, it was helpful. However: can anyone confirm that the baseline parameter in the "Precompute channel measures" window actually removes the baseline from the data? Because I just assumed it, but could not find it in any tutorial.</span></div><div class="qtdSeparateBR"><br><br></div><div class="yahoo_quoted" style="display: block;"><div style="font-family: 'bookman old style', 'new york', times, serif; font-size: 14pt;"><div style="font-family: HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif; font-size: 12pt;"><div dir="ltr"><font size="2" face="Arial">El Jueves, 28 de agosto, 2014 22:27:51, bjj2909102003 <<a href="mailto:bjj2909102003@163.com">bjj2909102003@163.com</a>> escribió:<br></font></div><br><br><div class="y_msg_container"><div id="yiv2074374669"><div><font face="\bookman old style\, \new york\, times, serif"><span style="background-color: rgb(255, 255, 255);"><span></span>Hello,Angel.</span></font></div><div><font face="\bookman old style\, \new york\, times, serif"><span style="background-color: rgb(255, 255, 255);">Firstly, if you already had baseline correction, it was not necesssary to repeat. And even you repeated it, it did not bring big influences for your data.</span></font></div><div><font face="\bookman old style\, \new york\, times, serif">Secondly,in my opinion, <span style="line-height: 28px;">precompute ERPs was necessary for guys who did not have baseline correction.</span></font></div><div><font face="\\bookman old style, new york, times\, serif"><span style="line-height: 28px;">In a word, </span><span style="line-height: 28px;">precompute ERPs(baseline correction) is reasonable!</span></font></div><div><br></div><hr size="1" align="left" style="width: 210px; height: 1px;"><div><span>bjj2909102003</span></div><blockquote style="margin-top: 0px; margin-bottom: 0px; margin-left: 0.5em;"><div> </div><div style="border-style: solid none none; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding: 3pt 0cm 0cm;"><div style="padding: 8px; font-size: 12px; font-family: tahoma; background-color: rgb(239, 239, 239);"><div><b>From:</b> <a rel="nofollow" ymailto="mailto:angeltabullo@yahoo.com" target="_blank" href="mailto:angeltabullo@yahoo.com" class="yiv2074374669">Angel Tabullo</a></div><div><b>Date:</b> 2014-08-27 23:13</div><div><b>To:</b> <a rel="nofollow" ymailto="mailto:eeglablist@sccn.ucsd.edu" target="_blank" href="mailto:eeglablist@sccn.ucsd.edu">eeglablist@sccn.ucsd.edu</a></div><div><b>Subject:</b> [Eeglablist] baseline correction</div></div></div><div><div class="yiv2074374669FoxDiv20140829091904585165"><div style="font-family: 'bookman old style', 'new york', times, serif; font-size: 14pt; background-color: rgb(255, 255, 255);"><div>Hi everyone! I have a doubt regarding how ERP manages baseline correction in individual datasets and study data. </div><div><br></div><div style="font-size: 19px; font-family: 'bookman old style', 'new york', times, serif; font-style: normal; background-color: transparent;">Everytime I epoch individual data, extract the epochs that correspond to each experimental condition and save them in separate datasets, I use the "Remove Baseline" Tool ("rmbase") to sustract the mean value of the prestimulus period from the epochs. However, EEGLAB offers another instance of baseline removal when precomputing channel measures for STUDY data. When you choose to precompute ERPs, you can indicate the time window for the baseline correction. My question is: is it necessary to repeat this baseline correction step when calculating the grand average with the study data if you already removed baseline mean values from individual epoched data?</div></div></div></div></blockquote></div><br><br></div></div></div></div></div>_______________________________________________<br>Eeglablist page:<span class="Apple-converted-space"> </span><a href="http://sccn.ucsd.edu/eeglab/eeglabmail.html">http://sccn.ucsd.edu/eeglab/eeglabmail.html</a><br>To unsubscribe, send an empty email to<span class="Apple-converted-space"> </span><a href="mailto:eeglablist-unsubscribe@sccn.ucsd.edu">eeglablist-unsubscribe@sccn.ucsd.edu</a><br>For digest mode, send an email with the subject "set digest mime" to<span class="Apple-converted-space"> </span><a href="mailto:eeglablist-request@sccn.ucsd.edu">eeglablist-request@sccn.ucsd.edu</a></div></blockquote></div><br></div></body></html>