Two-way repeated measures ANOVA

Two-way repeated measures ANOVA, for designs with two within-subjects variables.

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% function stats = rm_anova2(Y,S,F1,F2,FACTNAMES)
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% Two-factor, within-subject repeated measures ANOVA.
% For designs with two within-subject factors.
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% Parameters:
% Y dependent variable (numeric) in a column vector
% S grouping variable for SUBJECT
% F1 grouping variable for factor #1
% F2 grouping variable for factor #2
% FACTNAMES a cell array w/ two char arrays: {'factor1', 'factor2'}
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% Y should be a 1-d column vector with all of your data (numeric).
% The grouping variables should also be 1-d numeric, each with same
% length as Y. Each entry in each of the grouping vectors indicates the
% level # (or subject #) of the corresponding entry in Y.
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% Returns:
% stats is a cell array with the usual ANOVA table:
% Source / ss / df / ms / F / p
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% Notes:
% Program does not do any input validation, so it is up to you to make
% sure that you have passed in the parameters in the correct form:
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% Y, S, F1, and F2 must be numeric vectors all of the same length.
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% There must be at least one value in Y for each possible combination
% of S, F1, and F2 (i.e. there must be at least one measurement per
% subject per condition).
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% If there is more than one measurement per subject X condition, then
% the program will take the mean of those measurements.
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% Aaron Schurger (2005.02.04)
% Derived from Keppel & Wickens (2004) "Design and Analysis" ch. 18
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