Hello,
The raw statistic contains the TFCE scores for the unpermuted-data ( permutation 1 ). By permuting, randomise is able to generate the null-distribtution for these TFCE scores and so calculate p-values for the original ( raw ) statistic image. It is mostly far more appropriate to present these p-values than the raw TFCE-scores.
Many Regards
Matthew
> Hello TBSS experts,
>
> I have a question concerning how valid it is to present raw test statistics.
>
> After running randomise I get the three following thresholding/output options:
> a) _tfce_corrp_tstat (FWE - TFCE corrected for multiple comparisons)
> b)_tfce_p_tstat (TFCE - uncorrected for multiple comparisons)
> c)_tfce_tstat (TFCE - raw test statistic)
>
> In the literature, it is common that both corrected and uncorrected TBSS results (voxel-wise and TFCE) are presented with the latter validation of an application of a ROI analysis, in the regions identified as having statistically significant differences.
>
> So my question is, can one present these _tfce_tstat (TFCE - raw test statistic) results and use a ROI analysis to back them up or is this inappropriate?
>
> Additionally, could someone please point me in the right direction as where to read up on these "raw test statistics" because I can't find any information in the archives or in the randomise manual.
>
> Thank you for your insight and help,
>
> Georgios Alexandrou M.D.
> Karolinska Institute
> Astrid Lindgren Children's Hospital,
> Stockholm, Sweden
>
