Users, programmers, and statistical software

Statistical software provides essential support for statisticians and other s who are analyzing data or doing research on new statistical techniques. T hose supported typically regard themselves as "users" of the software, but as soon as they need to express their own ideas computationally, they in fa ct become "programmers." Nothing is more important for the success of stati stical software than enabling this transition from user to programmer, and on to gradually more ambitious software design. What does the user need? Ho w can the design of statistical software help? This article presents a numb er of suggestions based on past experience and current research. The evolut ion of the S system reflects some of these opinions. Work on the Omegahat s oftware provides a promising direction for future systems that reflect simi lar motivations.