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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Dear Fedrica,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Yes it is. You can get to the same outcome directly by just specifying cfg.keeptrials=’no’ (the default), but I assume you want to do some single-trial
analysis later on.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Best,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Stan<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> fieldtrip-bounces@science.ru.nl [mailto:fieldtrip-bounces@science.ru.nl]
<b>On Behalf Of </b>Federica Mauro<br>
<b>Sent:</b> woensdag 27 mei 2015 11:28<br>
<b>To:</b> FieldTrip discussion list<br>
<b>Subject:</b> [FieldTrip] Power Spectra - averaging across samples<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">Dear all,<o:p></o:p></p>
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<p class="MsoNormal">I have a question about spectral power computation.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">I'm using this code<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">cfg = [];<br>
cfg.output = 'pow';<br>
cfg.method = 'mtmfft';<br>
cfg.taper = 'hanning';<br>
cfg.foi = 5:1:40;<br>
cfg.t_ftimwin = 5./cfg.foi;<br>
cfg.tapsmofrq = 5;<br>
cfg.keeptrials = 'yes';<br>
cfg.channel = {'Fp1' 'Fp2' 'F7' 'F3' 'Fz' 'F4' 'F8' 'T3' 'C3' 'Cz' 'C4' 'T4' 'T5' 'P3' 'Pz' 'P4' 'T6' 'O1' 'O2'};<br>
freqfourier = ft_freqanalysis(cfg, eeg);<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">and the power spectrum output is a matrix 138 (samples) X 19 (electrodes) X 36 (frequencies), for each subject.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">My question is: is it correct to average the data across the samples dimension?<o:p></o:p></p>
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<p class="MsoNormal">Thank you in advance!<o:p></o:p></p>
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<p class="MsoNormal">Best,<o:p></o:p></p>
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<p class="MsoNormal">Federica<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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