Under the "Statistical power" heading, the overlapping distribution diagram is mis-labeled. The "Power (1 - beta)" label should be applied to the remaining portion of the right distribution (H_A, yellow) instead of the the left distribution (H_0, blue).
Under the "Statistical power" heading, the overlapping distribution diagram is mis-labeled. The "Power (1 - beta)" label should be applied to the remaining portion of the right distribution (H_A, yellow) instead of the the left distribution (H_0, blue).