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Hi all,</div>
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I wonder if anyone can clear up some confusion regarding evaluation of summed-cluster statistics following permutation. </div>
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Specifically, as of Maris and Oostenveld (2007), evaluation is performed for all clusters, based on the permutation distribution of the max (absolute) cluster statistic, see "It is important to note that the
<i>p</i>-values for all eight clusters are calculated under the permutation distribution of the maximum (absolute value) cluster-level statistic and not under the permutation distribution of the second largest, third largest, etc."</div>
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However, when I look at the guide at <a href="https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.fieldtriptoolbox.org%2Ftutorial%2Fstats%2Fcluster_permutation_timelock%2F&data=05%7C02%7Cfieldtrip%40science.ru.nl%7Cc286b1b639a44637f3cb08dda9baac6a%7C084578d9400d4a5aa7c7e76ca47af400%7C1%7C0%7C638853341443666306%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=8jWOCE9FriFeev2QrmHblQCuTfly1gDKVKM2gnjKSXk%3D&reserved=0" originalSrc="https://www.fieldtriptoolbox.org/tutorial/stats/cluster_permutation_timelock/" id="OWAbb86689d-8b00-6bcd-cd04-5d15de63247c" class="OWAAutoLink">
https://www.fieldtriptoolbox.org/tutorial/stats/cluster_permutation_timelock/</a></div>
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the following recommendation is given: And third, the critical value for the cluster-level test statistic (determined by cfg.alpha; see further) is now two-sided: negative cluster-level statistics must be compared with the negative critical value, and positive
cluster-level statistics must be compared with the positive critical value.</div>
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To me, these two statements seem contradictory. Please could someone clarify the correct approach (I assume the latter) and why the discrepancy?</div>
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Thanks,</div>
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Oliver</div>
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<p class="elementToProof">-------------------</p>
<p class="elementToProof">Oliver Hermann</p>
<p class="elementToProof">PhD Researcher</p>
<p class="elementToProof">Department of Psychology</p>
<p class="elementToProof">University of Bath</p>
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