Hi Gabriel, I've attached a matlab routine which will compute the PCC. If you cd into the GLM dir, then

X = load('Xg.dat'); beta = MRIread('beta.mgh'); C = load('yourcontrast/C.dat'); rvar = MRIread('rvar.mgh');

betamat = fast_vol2mat(beta); rvarmat = fast_vol2mat(rvar);

rhomat = fast_glm_pcc(betamat,X,C,rvarmat);

rho = beta; rho.vol = fast_mat2vol(rhomat,rho.volsize); MRIwrite(rho,'yourcontrast/pcc.mgh')

The R2 should just be the square of the PCC, right?

For the standardized beta, do you just divide the beta by sqrt(rvar)?

doug

On 3/14/13 1:39 PM, Gabriel Gonzalez Escamilla wrote:

Dear Freesurfers

I'm performing regression analyses including confounding variables, and I would like to know how to obtain the following information:

A) The squre R

and

B) The standarized beta coefficient of an independient variable; and the partial correlation with its p-values

Many thanks in advanced, Gabriel

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