Section 3: Factorial Designs

Analyzing several factors simultaneously: factorial designs.

Many experiments involve this study of two or more factors,
) like temperature, pH and concentration during an enzymatic reaction;
) the route and the hour of the day on the total time to commute from home to work;
) and sugar and butter amounts and oven temperature in a cookie recipe.

A factorial design means that in each complete trial or replicate of the experiment, all possible combinations of the levels of the factors will be investigated.
If there are “a” levels of factor A and “b” levels of factor B, each complete replicate will involve ab treatments, and we call it a crossed factorial design.