thank you!

- Thread starter ChrisMiller
- Start date

thank you!

why I can't get interactive effects in a two-way ANOVA without replication. Perhaps it's a basic misunderstanding of the test.

ie in 2 x 2 study with no reps you got df = 3: 1 for factor 1 + 1 for factor 2 + (2-1)*(2-1) for interaction, but oops you got nothing for error now. what you do? you drop error term: ie assume no interaction.

This is grossly different from that though, as you have proportions. your probably feeding arcsine(p) into ANOVA model? Maybe. But just use R function 'glm(..., family=binomial, weight=15', that's going to be easier, honestly i can't remeber how the formulas work out, that's what software is for.

In sas it would be proc genmod; model #survived/15 = temperature | time / link=logit;

can't go wrong the software will guide you to the right answer, and you can check it out by hand if you doubt it, or have some curiosity on the subject which you seem to.

you probably can do it with arcsine and anova, but i think you have to trick the software regarding the degrees of freedom. well maybe you can figure that out and teach me.