3dRegAna


This program performs multiple linear regression analysis.

Usage:
3dRegAna
-rows n                             number of input datasets
-cols m                             number of X variables
-xydata X11 X12 ... X1m filename    X variables and Y observations
  .                                   .
  .                                   .
  .                                   .
-xydata Xn1 Xn2 ... Xnm filename    X variables and Y observations

-model i1 ... iq : j1 ... jr   definition of linear regression model;
                                 reduced model:
                                   Y = f(Xj1,...,Xjr)
                                 full model:
                                   Y = f(Xj1,...,Xjr,Xi1,...,Xiq)

[-diskspace]       print out disk space required for program execution
[-workmem mega]    number of megabytes of RAM to use for statistical
                   workspace  (default = 750 (was 12))
[-rmsmin r]        r = minimum rms error to reject constant model
[-fdisp fval]      display (to screen) results for those voxels
                   whose F-statistic is > fval

[-flof alpha]      alpha = minimum p value for F due to lack of fit


The following commands generate individual AFNI 2 sub-brick datasets:

[-fcoef k prefixname]        estimate of kth regression coefficient
                               along with F-test for the regression
                               is written to AFNI `fift' dataset
[-rcoef k prefixname]        estimate of kth regression coefficient
                               along with coef. of mult. deter. R^2
                               is written to AFNI `fith' dataset
[-tcoef k prefixname]        estimate of kth regression coefficient
                               along with t-test for the coefficient
                               is written to AFNI `fitt' dataset


The following commands generate one AFNI 'bucket' type dataset:

[-bucket n prefixname]     create one AFNI 'bucket' dataset having
                             n sub-bricks; n=0 creates default output;
                             output 'bucket' is written to prefixname
The mth sub-brick will contain:
[-brick m coef k label]    kth parameter regression coefficient
[-brick m fstat label]     F-stat for significance of regression
[-brick m rstat label]     coefficient of multiple determination R^2
[-brick m tstat k label]   t-stat for kth regression coefficient

[-datum DATUM]     write the output in DATUM format.
                   Choose from short (default) or float.


N.B.: For this program, the user must specify 1 and only 1 sub-brick
      with each -xydata command. That is, if an input dataset contains
      more than 1 sub-brick, a sub-brick selector must be used, e.g.:
      -xydata 2.17 4.59 7.18  'fred+orig[3]'

INPUT DATASET NAMES
-------------------
This program accepts datasets that are modified on input according to the
following schemes:
  'r1+orig[3..5]'                                    {sub-brick selector}
  'r1+orig<100..200>'                                {sub-range selector}
  'r1+orig[3..5]<100..200>'                          {both selectors}
  '3dcalc( -a r1+orig -b r2+orig -expr 0.5*(a+b) )'  {calculation}
For the gruesome details, see the output of 'afni -help'.

++ Compile date = Oct 17 2024 {AFNI_24.3.03:linux_ubuntu_24_64}