Statistics of data grouped by factors
This process lies in finding statistics which consist of more than one variable, grouped or crossed by factors. The table must be organized by columns between variables and factors.
tapply.stat(y, x, stat = "mean")
stat method = "mean", ...
Denismar Alves Nogueira
Eric Batista Ferreira
Portya Piscitelli Cavalcanti
(Adapted from Felipe de Mendiburu - GPL)