help > two questions about NiiStat functionality
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Mar 14, 2018  03:03 PM | jayapad
two questions about NiiStat functionality
Hi, I have two questions about NiiStat functionality:

1) Is there a way to covary for variables other than lesion size? My understanding is that there isn't... If I put multiple variables into my Excel spreadsheet, my sense is that NiiStat produces an analysis and file for each variable, but that these analyses are not 'controlling for' the remaining variables in this spreadsheet. So if I say, have a column for age and a neuropsych scale, the output for the neuropsych measure has not controlled for age. 

2) Is there a way to produce totally uncorrected results? I know this is not statistically proper, but we want to be able to show both our FDR corrected and uncorrected results.


Thanks very much!
Jaya
Jun 21, 2018  04:06 PM | Chris Rorden
RE: two questions about NiiStat functionality
1.) Nuisance regression is handled using the Freedman-Lane method. So you simply create a spreadsheet with multiple columns, and if you specify Freedman-Lane permutation you will get a result for how well each column is associated with the neuroimaging data afte rthe variability of the other columns are factored out
 https://www.nitrc.org/plugins/mwiki/index.php/niistat:MainPage#Number_of_permutations

2.) When you conduct an analysis, you will get a thresholded image as well as an unthresholded image:

threshZlesion_*.nii
Zlesion_*.nii