An example of a scientific investigation design that uses independent variable and dependent variable in its design is a research that seeks to find out the effect of two different fertilizers on the growth of a tuber crop (yam). The independent variable in this case is the type of fertilizer used while the dependent variable is the corresponding growth of the tuber crop. In a research set up, the independent variable is the variable that causes a change in the dependent variable and the dependent variable is the one that is been measured.