ABSTRACT
Previous chapters have been concerned with experiments in which a single set of treatments was applied to the plots in a block design or in a row-column design. Suppose now that there are two different treatments, say temperature and pressure, and that their effect on the response of some chemical process is to be studied. One approach would be to carry out two separate experiments. One would be concerned with the effect produced by varying temperature levels, with pressure kept at some constant value. The other experiment would look at the effect produced by varying pressure levels with temperature now held constant.
