Behind every experiment is an instrument, and behind every instrument is a set of numbers that make its readings mean something. In this undergraduate-level text, students get a three-step approach to learning basic and advanced concepts, so the atmosphere it creates in the classroom and lab is non-threatening. However, it gets the job done by describing numbers and scales, models, frequency, distribution, tendencies, dispersion, norms, growth, tests, validity, reliability and even the ethics of testing. The result is a slim volume with potential for use among social science students and others with only a casual understanding of data gathering techniques. Annotation ©2005 Book News, Inc., Portland, OR (booknews.com)