Dear Statalists,
Can anyone give me some guidance as to how to calculate the required sample
size for the following two-way within-subjects design?
Planned parameters of the experiment are:
(1) two independent variables, one with three levels and the other with six
levels,
(2) have each subject give two dependent measures of the same kind to two
different stimuli, e.g., does he like condition A first and does he like
condition B second; each condition is a combination of the two independent
variables,
(3) the dependent variable is a discrete variable (yes/no)
(4) pair-wise two-tailed tests of proportions
(5) alpha=.05, beta=.2, correlation between responses to any two stimuli
ranges from 0.1 to 0.3
Thank you very much.
Jordan Lin
Center for Food Safety and Applied Nutrition
Food and Drug Administration
5100 Paint Branch Parkway, HFS-727
College Park, MD 20740
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