Dear Christine Smith,
Below is an answer you had written about my previous question. Thank you so much!

I was just unclear about what you meant with "load your threshold subbrick in the lower subbrick selector within the afni define function window, and your amplitude in the
first subbrick selector"

Right now, I have been loading my Anatomy dataset with the MannWhitney test as the functional overlay but I was not sure which subbrick of the mann whitney test lay where. is there a specification for which subbrick I am looking at, at a given time?

Also, "Slide the threshold slider until your p value displays .001", does this mean the number next to the slider is the p-value and the number directly below this (at the base of the threshold slider) is the actual threshold or is it the other way around? becasuse the number at the base does not reach below .3174, and I need a p-value of .05. Sorry, these are silly questions, I'm just confused.

Finally, in the alpha sim test results, the alpha value is the actual result of the test, so to find out the cluster volume for the p-value .05, would I need to look at the alpha value of .0500 and the corresponding cluster?

Thank you so much for your help so far!
Ellen



Below is your answer to a previous question I had:

Author: Christine Smith (---.ucsd.edu)
Date: 12-08-03 14:12

To use your alpha sim results, you need to find the mann-whitney statistic associated with p=.001. To find this number load
your threshold subbrick in the lower subbrick selector within the afni define function window, and your amplitude in the
first subbrick selector. Slide the threshold slider until your p value displays .001. Use this mann-whitney statistic
number in your -1thresh option in 3dmerge, along with your minimum cluster size of 1058. The resulting clusters >= to 1058
will have a p value of .05.

Your thinking souds right, so far.
Christine Smith