The illustrations in this article are intended to show some of what is possible in the way of providing a reasonable GUI for working with power and sample size. The key objectives are to make the interface as straightforward as possible, and to keep it as uncluttered and nontechnical as possible.
Workbooks designed for one scenario are easily modifiable or extended to others.
A typical spreadsheet application relies on formula cells and data cells. To get a cleaner, less cluttered interface like in Figure 3 we need cells to serve both roles, requiring programming as extensive in Excel as in Java. By taking advantage of parameter tags, one can develop general-purpose applets. It is possible for a statistical consultant to write a script like the one in Figure 5 and then to provide it to a researcher over the Internet. There is much more that can be done.