SAS for Mixed Models, Second Edition, 2nd Edition

4.6 Example: Type × Dose Response

This example involves data from an experiment to compare the response of two plant varieties to increasing amounts of pesticide designed to protect the plants against disease. The experiment was conducted in a greenhouse. Plants were placed on five benches, which were used as blocks to account for local variation in the greenhouse. Each bench was divided into four sections where, for convenience, levels of the pesticide were applied. Each section had two plants, one of each variety. Data Set 4.6, “Variety-Pesticide Evaluation,” in Appendix 2, “Data Sets,” contains the data for this experiment. The variable TYPE denotes the variety, S for “susceptible” (a genotype susceptible to the disease) and R for “resistant”; ...