Maximize Systematic Variance:
The systematic variance is the variance or the difference caused in the dependent variable by the experimental variable. By maximizing the systematic variance means to magnify or makes evident the effect of the experimental variable on the dependent variable. The concept of variance and its control can be explained further on the basis of an example. Suppose a professor of sociology or an university administrator wants to improve the students performance in the class. For this he has to find a better method of imparting education. He makes the hypothesis that student reading habit is increased or their class performance is improved by the lecture method. In this example the experimental variable will be participation methods teaching the effect of which the professor or the administrator desires to measure as compared to the effect of lecture methods of teaching. Students performance is the dependent variable. In another study students reading habit can be taken as the dependent variable the experimental variable being the same.