||An experimental design identifies the independent, dependent, and nuisance variables and indicates the way in which the randomization and statistical aspects of an experiment are to be carried out. It refers to a plan for assigning subjects to experimental conditions and the statistical analysis with the plan. The design of an experiment to investigate a scientific or research hypothesis involves a number of interrelated activities: 1. Formulation of statistical hypothesis, 2. Determination of the experimental conditions to be used, and 3. Specification of the number of subjects required.