FSL group,
Relatively new to FSL, I am proceeding through some of the lectures and practicals online. I have a basic theory question regarding the feat1_part1 lecture.
I understand that FSL uses the GLM, but I am a little confused by a variable label β in the equation Yk = Xkβk + Єk. That is, how is β an effect size? Perhaps here it is analogous to R-squared?
Normally, in Yi= b0 + b1X1 + b2X2 … +bnXni + Є, the b-values are the coefficients of each predictor variable. In addition, β is reserved for standardized b-values (the number of standard deviations by which some outcome changes based on one standard deviation change in the predictor).
I apologize for the basic nature of this question. Perhaps there is a pervious string on the FSL list to which I can be referred.
Best,
Lance
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