New metrics needed for new generation: lines of code, function points won't do at the dawn of the graphical, object era - computer-aided software engineering: includes related article on Windows test tools and a glossary on metrics for object oriented design - Buyers Guide

Software Magazine, May, 1992 by Jessica Keyes

This emphasis on quality is demonstrated by Unisys' commitment to producing products that can be used both internally and externally for automatic testing. For example, the Unisys Linc Interpretive Test Environment is Case software that eliminates the need to regenerate systems during the test stage of application creation. Unisys Linc developers can change code and immediately verify proper operation to implement changes faster. This interpretive test environment comes with an online debugger for locating, analyzing, testing and correcting logic errors, as well as a statistics gathering feature to ensure code efficiency.

At the other end of the spectrum, Unisys has played a pivotal role in the funding of function-point measurement research by Dr. Eberhard Rudolph, professor of information systems at the Hochschule Bremerhaven in Bremerhaven, Germarny. He is a well-known authority on productivity in application software development, in particular fourth-generation languages (4GLs), Case tools and the function-point technique. His most recent study, released in November 1991, surveyed the effectiveness of the Unisys Linc software development environment.

According to the study, "The results indicate that Linc users can develop larger application systems than installations using conventional Cobol environments. Productivity gains of 5:1 to 10:1 were observed for application systems exceeding 2,000 function points. Applications over 5,000 function points can have gains of 20:1 and more."

Though and Rudolph study measured just the Unisys Linc environment, one can extrapolate that the newer software methods can play a large role in fostering productivity.

Digital Equipment Corp., located in Maynard, Mass., is another hardware/software vendor with a need for consistent quality and enhanced productivity across hardware platforms and software types. Tom Harris, software engineering group manager for the Commercial Languages and Tools group, based in Nashua, N.H., is responsible for software developed across all platforms. In his long tenure at DEC he has managed the development of Motif, compilers and Case tools, as well as project management ystems.

Over the years, Harris has refined some techniques that he uses to develop quality software. The most important of these techniques is a clear definition, at the outset of the project, of its usability goals. "If you are developing a spreadsheet, how will you know that someone can use it effectively? What other products will this be positioned against? What are some sample tasks? And is the rate at which you do these tasks important?" he said.

Harris arrives at these goals by working with his customers. "As it turns out," he said, "this is a study in human factors."

In performing this human factors study, Harris and his staff have developed a number of techniques ranging from knowledge acquisition to development of quantifiable measurement parameters. One of these is what Harris refers to as "contextual inquiry," which studies the worker in the context of doing his or her job, rather than putting that worker in a lab setting.