SAS Code for Recovering Intereffect Information in Experiments with Incomplete Block and Lattice Rectangle Designs

Efficient use of resources and time requires optimal planning of designed experiments and optimal recovery of information from them. Selection of an appropriate experiment design and selection of an appropriate statistical analysis are mandatory for efficient experimentation. It is known that using a random effects model is more efficient than using a fixed effects one, as in the analysis of variance, meaning that fewer experimental units (plots) will be necessary to obtain the same precision. The question of transformation of data prior to analysis, of using standard textbook analyses, or of using a form of spatial analysis arises with each experiment. To obtain these analyses, it is desirable that computer programs (code) be available to the experimenter. Computer programming to recover the information from random effects is not well or widely understood. In light of recent developments of software for performing the needed calculations, a description of SAS programs is presented. Code is described for recovering interblock, interrow, intercolumn, intergradient, and interregression information in incomplete block and lattice rectangle (row‐column arrangement within each complete block) designed experiments. These are illustrated with a numerical example.