After you click either One Sample Mean, or Two Sample Means in the initial Sample Size selection list (Sample Size and Power Choices), a Sample Size and Power window appears. (See Initial Sample Size and Power Windows for Single Mean (left) and Two Means (right).)

The initial Sample Size and Power window requires values for Alpha, Std Dev (the error standard deviation), and one or two of the other three values: Difference to detect, Sample Size, and Power. The Sample Size and Power platform calculates the missing item. If there are two unspecified fields, a plot is constructed, showing the relationship between these two values:

runs a JSL script that displays an interactive plot showing power or sample size. See the section, Sample Size and Power Animation for One Mean, for an illustration of the animation script.