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Two Groups (One Factor/Two Levels), One Covariates

This models the input as two lines. If DODS, then each line has its
own intercept and slope. If DOSS, then each line has its
own intercept but they share a slope.

FSGD File: example3.fsgd
{{{
GroupDescriptorFile 1
Title OSGM
Class Group1
Class Group2
Variable Age
Input subject1 Group1 30
Input subject2 Group2 40
}}}

Nclasses = 2
Nvariables = 1

DODS =================================================
Regressors:
Nregressors = Nclasses*(Nvariables+1) = 2*(1+1) = 4
Regressor1: ones for subjects in Group 1, 0 otherwise. Codes intercept/mean for Group 1
Regressor2: ones for subjects in Group 2, 0 otherwise. Codes intercept/mean for Group 2
Regressor3: age for subjects in Group 1, 0 otherwise. Codes age slope for Group 1
Regressor4: age for subjects in Group 2, 0 otherwise. Codes age slope for Group 2

Contrasts:

Contrast1: ------------
Null Hypothesis: is there a difference between the group intercepts?

Contrast File: g1-g2.intercept.mtx
--------------- cut here --------------
1 -1 0 0
--------------- cut here --------------

Since this is a t-test, the output will be signed, with Group1>Group2
being positive (red/yellow). Reversing the sign will only change the
sign of the output, not its magnitude.

Contrast2: ------------

Null Hypothesis: is there a difference between the group slopes? Note:
this is an interaction between group and age. Note: not possible to
test with DOSS

Contrast File: g1-g2.slope.mtx
--------------- cut here --------------
0 0 1 -1
--------------- cut here --------------

Since this is a t-test, the output will be signed, with Group1>Group2
being positive (red/yellow). Reversing the sign will only change the
sign of the output, not its magnitude.

Contrast3: ------------
Null Hypothesis: does Group1 differ from Group2 in intercept or slope?

Contrast File: g1-vs-g2.mtx
--------------- cut here --------------
1 -1 0 0
0 0 1 -1
--------------- cut here --------------
Note: this is an F-test (and hence unsigned).

Contrast4: ------------
Null Hypothesis: does mean of group intercepts differ from 0?

Contrast File: g1g2.intercept.mtx
--------------- cut here --------------
0.5 0.5 0 0
--------------- cut here --------------

Contrast5: ------------
Null Hypothesis: does mean of group slopes differ from 0?

Contrast File: g1g2.intercept.mtx
--------------- cut here --------------
0 0 0.5 0.5
--------------- cut here --------------		 ~+'''One Group, One Covariate'''+~

One Group, One Covariate

Fsgdf1G1V (last edited 2010-09-20 15:10:27 by MartinReuter)