A TOOLKIT FOR APPRAISING THE LONG-TERM USABILITY OF A TEXT EDITOR

We describe a large-scale, low-cost, project that has examined the way people develop their skill in using fundamental software tools. The study involved over 2000 users during a three-year period of use of the sam text editor. The work took place while the editor was being employed in normal day to day work - it was not a laboratory experiment. Our main contributions are first to demonstrate very long-term, low-cost monitoring with collections of simple analysis tools. Second, we have started to develop an understanding of how usability changes in the long term. Third, studies of usability often concentrate on assessment before a system is released for widespread use, whereas ours can help inform the long-term design of new tools - a different dimension of usability. In addition we have mixed snap-shot studies with descriptions of long-term, gradual change. We can track the full development of the user, even though the quality of the data is lower than that normally associated with usability studies.