Consider the plot of power as a function of effect size for the two-sample t-test shown in Figure 4.3.

a. Create a plot to show power as a function of both effect size and sample size while keeping other parameters fixed.

b. The curve is shaped like an inverted bell curve, or a "bathtub" shape. Interpret the shape of the curve.

Data from Figure 4.3

Transcribed Image Text:

Power 1.0 0.9- 0.8- 0.7- 0.6- 0.5- 0.4- 0.3 0.2- 0.1 0.0- -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 Effect Size