Jim,
You are not missing something elementary, in fact, you have found an elementary problem in qdec that was overlooked until now.
The 'Regression Coefficient' scalar display is the file beta.mgh found in your results directory (ie qdec/Untitled, usually). That file contains a frame of data for each regressor. The oversight was that qdec happens to only display the first frame. The regressors in beta.mgh are ordered the same as that in the contrast matrix, so whatever that first regressor is is the one you are seeing. qdec as it is now doesn't print-out the regressors (columns of contrast matrix) in text form, but a future version will (and will also allow selecting the other regressor coefficients).
Nick
On Tue, 2008-04-01 at 13:36 -0500, James N Porter wrote:
Hello All-
When viewing the scalar overlays in qdec, how do I tell which coefficient is being displayed when I select "Regression Coefficients" from the menu? Having more than one regressor, I would expect more than one overlay of coefficients. Am I missing something very elementary?