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Testing Loss and Gain of Statistical Power

Surface quality can be tested by tracking change in statistical power between groupstats results of the ADNI60 and Buckner40 subject sets. The test diff_power, currently located in utils/test/diff_power, computes differences in significance and locates surfaces regions with the largest change. Given a source and reference groupstats test (i.e. thickness of controls vs ADs in dev and stable6), diff_power does the following:

Subtracts the ref sig.mgh from the src sig.mgh (producing sigdiff.mgh) and masks any vertices that did not gain or lose significance (default threshold: p=0.05)
Computes clusters from the masked sigdiff.mgh and locates the vertex of peak change (in either direction) for each cluster
For the largest n_c clusters, finds the difference in thickness (between the dev and stable6) for each individual subject at the peak vertex
For the top n_s subjects with the greatest thickness difference, maps the peak vertex from fsaverage to the dev and stable6 white and pial surfaces and computes the distance between the two
The results are stored in a summary.log file and a script called inspect.sh is created to automatically point the user to the surface regions in question

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1. Subtracts the ref sig.mgh from the src sig.mgh (producing sigdiff.mgh) and masks any vertices that did not gain or lose significance (default threshold: p=0.05) 2. Computes clusters of change in significance and locates the peak sigdiff.mgh vertex for each cluster	1. Subtracts the ''ref'' sig.mgh from the ''src'' sig.mgh (producing sigdiff.mgh) and masks any vertices that did not gain or lose significance (default threshold: p=0.05) 2. Computes clusters from the masked sigdiff.mgh and locates the vertex of peak change (in either direction) for each cluster 3. For the largest ''n,,c,,'' clusters, finds the difference in thickness (between the dev and stable6) for each individual subject at the peak vertex 4. For the top ''n,,s,,'' subjects with the greatest thickness difference, maps the peak vertex from fsaverage to the dev and stable6 white and pial surfaces and computes the distance between the two 5. The results are stored in a {{{summary.log}}} file and a script called {{{inspect.sh}}} is created to automatically point the user to the surface regions in question