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å-acontr: Estimates contrasts among levels of factor ÔaÕ
íE.g., t-tests are conducted among levels of the factor ÒStimulus ConditionÓ to determine if their percent signal changes differ significantly from each other throughout the brain
íHere are some contrasts we performed:
í
í TM    HM TP       HP          voxel-by-voxel t-tests:
í 0      1 0         -1      Þ Human Movies vs. Human Points
í 1      0 -1          0      Þ Tool Movies vs. Tool Points
í 0      0 1         -1      Þ     Tool Points vs. Human Points
í 1     -1 0          0       Þ     Tool Movies vs. Human Movies
í -1      1         -1         1      Þ Tools vs. Humans
í 1      1 -1         -1      Þ Movies vs. Points
í
íFor simple contrasts, you could also use the -adiff option                    (e.g., -adiff 2 4)
í Tools vs. Humans contrast collapses across Animation Type               (i.e., Movies and Points)
í Movies vs. Points contrast collapses across Object Type                      (i.e., Tools and Humans)