A couple of people have pointed out that the notes I posted over the weekend describe a 3x2 contingency table (3 maternal genotypes, 2 paternal alleles). Explanations of contingency tables typically talk about 2x2 tables, which has caused some confusion.
The principles are the same. In both cases we're asking whether the proportions of outcomes are the same across categories. In this case, we're asking whether the proportion of patern A1 alleles (Est-F) is the same across the three maternal genotype frequencies. Computer packages like R, SAS, SPSS, JMP, Stata, and the like know how to do the more complicated calculation. The difference between a 3x2 test and a 2x2 test is like the difference between an ANOVA and a t-test.
If this isn't clear yet (or if I've made things worse), ASK A QUESTION.
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