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<font size="-1"><font face="Arial">Dear all,</font></font><br>
I apologize if this has been asked before, or else is too trivial.<br>
<br>
I have been trying to understand how the the pymvpa2 toolbox
calculates the chi-square test of a confusion matrix.<br>
<br>
In a cross-validation (e.g., cvte.ca.stats), it seems that by
default this is done by means of a one-dimensional Goodness-of-fit
chi-square test with expected uniform frequency distribution.<br>
<br>
I was wondering whether the bi-dimensional Pearson's chi square
wouldn't be more appropriate, as it seems to me that this would more
closely reflect the "predictions vs targets N x N" matrix structure.<br>
<br>
Thank you and very best wishes,<br>
Marco<br>
<br>
<pre class="moz-signature" cols="80">--
Marco Tettamanti, Ph.D.
Nuclear Medicine Department & Division of Neuroscience
IRCCS San Raffaele Scientific Institute
Via Olgettina 58
I-20132 Milano, Italy
Phone ++39-02-26434888
Fax ++39-02-26434892
Email: <a class="moz-txt-link-abbreviated" href="mailto:tettamanti.marco@hsr.it">tettamanti.marco@hsr.it</a>
Skype: mtettamanti</pre>
<br>
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