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Dear Expert:
If I want to examine whether there are any differences in the slopes of FA with Age among three groups, would the following matrix and contrasts work for me? (As an example below, 3 subjects per group, and the age will be demeaned)

EV1             EV2            EV3            EV4            EV5            EV6  
G1              G2              G3           AgeG1      AgeG2    AgeG3
1                  0                  0                 20                  0                  0
1                  0                  0                 18                  0                  0
1                  0                  0                 16                  0                  0
0                  1                  0                  0                   12                 0
0                  1                  0                  0                   15                 0
0                  1                  0                  0                   19                 0
0                  0                  1                  0                    0                  21
0                  0                  1                  0                    0                  17
0                  0                  1                  0                    0                  14


Contrasts:                             EV1    EV2   EV3   EV4   EV5   EV6
C1: SlopeG1 > SlopeG2      0        0        0         1         -1        0    
C2: SlopeG1 < SlopeG2      0        0        0        -1          1        0
C3: SlopeG2 > SlopeG3      0        0        0          0          1       -1
C4: SlopeG2 < SlopeG3      0        0        0          0         -1        1
C5: SlopeG1 > SlopeG3      0        0        0          1           0      -1
C6: SlopeG1 < SlopeG3      0        0        0         -1          0        1


Thank you very much,
Yuwen