www.gusucode.com > stats 源码程序 matlab案例代码 > stats/TwoWayANOVAExample.m
%% Two-Way ANOVA %% % Load the sample data. % Copyright 2015 The MathWorks, Inc. load popcorn popcorn %% % The data is from a study of popcorn brands and popper types (Hogg 1987). % The columns of the matrix |popcorn| are brands, Gourmet, National, and % Generic, respectively. The rows are popper types, oil and air. In the % study, researchers popped a batch of each brand three times with each popper, that is, the % number of replications is 3. The first three rows correspond to the oil % popper, and the last three rows correspond to the air popper. The response % values are the yield in cups of popped popcorn. %% % Perform a two-way ANOVA. Save the ANOVA table in the cell array |tbl| for % easy access to results. [p,tbl] = anova2(popcorn,3); %% % The column |Prob>F| shows the _p_-values for the three brands of popcorn % (0.0000), the two popper types (0.0001), and the interaction between brand % and popper type (0.7462). These values indicate that popcorn brand % and popper type affect the yield of popcorn, but there is no evidence of % an interaction effect of the two. %% % Display the cell array containing the ANOVA table. tbl %% % Store the _F_-statistic for the factors and factor interaction in % separate variables. Fbrands = tbl{2,5} Fpoppertype = tbl{3,5} Finteraction = tbl{4,5}