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Hi Donald - I know this may seem rather obvious, but could you tell me where in the bottom left of the table is the minimum cluster size that has a cluster corrected p-value less than 0.05? Is this the same thing as the 'extent threshold k = 0 voxels' that I see at the bottom left of the table? I expect this is because I put in 0 under the extent threshold in the results tab. Also, how can I cluster FDR from the table? And what is FDR? I only see in the results table a FDRp value and FDRc? I'm attaching a screenshot of my results table for reference. Thanks and apologize for my extensive questioning :-P Joelle On Tue, Aug 11, 2015 at 2:58 PM, MCLAREN, Donald <[log in to unmask]> wrote: > In the results table, the bottom left of the table provides the minimum > cluster size that has a cluster corrected p-value less than 0.05. You can > then use this cluster size when you display the data and the clusters > showing will all be significant with the FWE control. You can also use > cluster FDR from the table (SPM) or 3dClustSim (afni) to determine the > cluster size to use. > > Best Regards, > Donald McLaren, PhD > > > On Tue, Aug 11, 2015 at 12:22 PM, Joelle Zimmermann < > [log in to unmask]> wrote: > >> Thanks Donald. How can I control the FWE at the cluster level in the GUI? >> - where can I find this option? >> >> On Tue, Aug 11, 2015 at 12:14 PM, MCLAREN, Donald < >> [log in to unmask]> wrote: >> >>> If you go with an uncorrected voxel criteria, which I suggest, then you >>> should correct for multiple comparisons by controlling the FWE at the >>> cluster level for publication. If its an intermediate analysis, controlling >>> the cluster-wise alpha is less of an issue. >>> >>> Best Regards, >>> Donald McLaren, PhD >>> >>> >>> On Tue, Aug 11, 2015 at 12:06 PM, Joelle Zimmermann < >>> [log in to unmask]> wrote: >>> >>>> Hi Donald, >>>> >>>> Good to hear from you again. Right, that's what I suspected about the >>>> first-level. I have 28 subjects in my dataset, and not seeing all that much >>>> at FWE. As long as there isn't a strict standard SPM people go with, I >>>> think .001 is better for me. >>>> >>>> Later I plan to split my 28 subjects into 2 groups so will have even >>>> fewer subjects. >>>> >>>> Thanks, >>>> Joelle >>>> >>>> On Tue, Aug 11, 2015 at 12:02 PM, MCLAREN, Donald < >>>> [log in to unmask]> wrote: >>>> >>>>> Statistical Thresholding at the first level has no impact on the >>>>> second-level data. >>>>> >>>>> For the second-level, it depends on how large the effect size you >>>>> expect to see and how many subjects you have in your dataset. >>>>> >>>>> Best Regards, >>>>> Donald McLaren, PhD >>>>> >>>>> >>>>> On Tue, Aug 11, 2015 at 10:58 AM, Joelle Zimmermann < >>>>> [log in to unmask]> wrote: >>>>> >>>>>> Hi Experts, >>>>>> >>>>>> I'm running a first-level analysis per subject, and then forwarding >>>>>> the .con images into a second-level analysis. >>>>>> >>>>>> I'm wondering if there is a standard way to set the p-value >>>>>> adjustment to control in the results tab for the first-level and the >>>>>> second-level analysis. For instance, would you recommend FWE for the >>>>>> first-level single subject analyses, and .001 for the second-level analysis? >>>>>> >>>>>> Thanks, >>>>>> Joelle >>>>>> >>>>>> >>>>>> >>>>> >>>> >>> >> >