glm.rfx_rmap
no way to compare when less than two revisions
Differences
This shows you the differences between two versions of the page.
— | glm.rfx_rmap [2010/05/29 01:55] (current) – created jochen | ||
---|---|---|---|
Line 1: | Line 1: | ||
+ | ====== GLM:: | ||
+ | ===== Motivation ===== | ||
+ | In the field of neuroscience, | ||
+ | |||
+ | For instance, if in a mathematical task (adding three two-digit numbers, for instance) strong differences between the performance of subjects is observed (measured by reaction time and error rate), it could be of interest to see if more successful subjects show relatively stronger activation (e.g. measured as per cent signal change of the BOLD response) in regions that seem to be relevant for the task. | ||
+ | |||
+ | There are different ways to approach this kind of question, one of which is employing simple regressions, | ||
+ | |||
+ | ===== Requirements ===== | ||
+ | This function is currently implemented for BrainVoyager QX's GLM format only. And the behavioral variable (data vector) must be available in the current workspace. | ||
+ | |||
+ | ===== Reference / glm.Help(' | ||
+ | < | ||
+ | |||
+ | | ||
+ | |||
+ | Input fields: | ||
+ | |||
+ | | ||
+ | | ||
+ | | ||
+ | .const | ||
+ | .meanr | ||
+ | .meanrmsk | ||
+ | .names | ||
+ | .rank flag, rank-transform data before regression | ||
+ | .robust | ||
+ | .subsel | ||
+ | .thresh | ||
+ | .voiidx | ||
+ | |||
+ | | ||
+ | |||
+ | | ||
+ | |||
+ | ===== Usage examples ===== | ||
+ | When the behavioral variable is available as **'' | ||
+ | |||
+ | * computing a simple regression with all subjects for the contrast '' | ||
+ | struct(' | ||
+ | * computing a rank-transformed correlation and auto-naming:< | ||
+ | struct(' | ||
+ | * computing a robust regression and also computing a t-contrast for the main effect after taking the variance explained by the behavior into account:< | ||
+ | struct(' | ||
+ | |||
+ | The resulting map (in this case VMP) can easily be stored via the [[obj.Save|Save]] or [[obj.SaveAs|SaveAs]] methods. |
glm.rfx_rmap.txt · Last modified: 2010/05/29 01:55 by jochen