ANOVA with One Within-subject Variable (2 of 4)

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Source      df         Ssq        Ms         F       p
 Subjects    3      1888.375   629.458
 Condition   1        15.125    15.125    121.00   0.002
 Error       3         0.375     0.125
Total        7      1903.875   271.982
Degrees of Freedom
The degrees of freedom for subjects is always N-1 where N is the number of subjects. For this problem: N-1 = 4 - 1 = 3.

The degrees of freedom for the independent variable (Condition) is always equal to the number of levels of the independent variable minus 1. For this example, the degrees of freedom is 2 - 1 = 1 since there are two conditions (experimental and control).

The degrees of freedom error is always the product of the degrees of freedom for Subjects and the degrees of freedom for the independent variable. For this example, the degrees of freedom is equal to 3 x 1 = 3. The degrees of freedom total is equal to the total number of numbers in the analysis minus 1. For this example, there are eight numbers so the degrees of freedom is equal to 8 - 1 = 7. Notice that the degrees of freedom for Subjects, Conditions, and Error add up to the degrees of freedom total 3 + 1 + 3 = 7.
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