Example of a one-sided t-test with 4 observations/subjects per group. The first column of the design matrix models Group 1, while the second models Group 2. 
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DESIGN MATRIX:
 1  0
 1  0
 1  0
 1  0
 0  1
 0  1
 0  1
 0  1

CONTRAST (Group 2 > Group 1):
 -1 1

STATISTICAL TEST:
t-test
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