ABSTRACT
This chapter explores several aspects of performance evaluation, beginning with some of the classical measures of system performance. It discusses methods of evaluating client satisfaction with the system and the overall service. Performance measurement and evaluation of information retrieval systems is a broad topic, with a large literature to support it. The chapter provides only a cursory overview of the issues most relevant to evaluating a searching service. Evaluating searching performance requires measuring both the searcher's ability to exploit the system and the searcher's ability to work with clients. Client satisfaction is perhaps the most difficult aspect to evaluate, since it is least under the searcher's control and is hard to quantify. System performance can be evaluated using any of a number of quantitative measures, the most popular of which are precision and recall. The quantitative measures applied to system performance are also useful in evaluating searching performance.
