Hello,
Im trying to run an analysis to establish the effect of three different training programmes on sprint speed (This initial ANOVA is below). Furthermore, I need to establish whether there is a different effect of the programmes for boys and for girls. How do I incorporate my 'Gender' variable into this code in order to split the analysis for boys and girls? I understand the by() function allows you to split by factors. But, don't understand how to work it into an ANOVA.
Sprint7<-aov(Postsprint ~ Prog, data = Sprint)
Anova(Sprint7, Type = "III")
summary (Sprint7)
Created on 2020-03-22 by the reprex package (v0.3.0)