Hi, all SPM users,
Now a days, I've been trying to do the correlation analysis in SPM8.
My experiemental context is the following.
First of all,
I computed the volume concentration between the patients(20 subjects) and the normal controls(20 subjects).
And then I wanted to know whether one factor (age) is correlated with the volume concentration of the patient group or not.
So, I chose 20 images (those are smoothed unmodulated) from User Interface of the "Basic models"
Then, I selected "multiple regression" as a statistics method.
And, then, I entered a covariate (a vector consisted of 20 values).
After this, I did set some questions
--> no grand mean scaling, threshold masking(absolute, 0.1), implicit mask(yes), global caculation(omit).
After finished all setting for "basic models",
I estimated by selecting "SPM.mat".
Next, from Results, I loaded "SPM.mat", then, defined contrast.
--> name: ageing effect
--> type: t-contrast
--> contrast: 0 1 (0: volume concentration, 1: ageing effect)
--> submit
After submitting, I tried three tests (FWE(0.05), FDR(0.05), Uncorrected(0.001)).
I'm very concerning about the above things.
Because I did try to find any good documents for "correlation analysis" in SPM.
But, I couldn't find any....
Please let me know whether my work is fine or not.
If it has some falses, give me any advices and tips...
Thanks,
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