In fields as varying as education, politics, and health care, assessment and the use of measurement and statistics have become an integral part of almost every activity undertaken. These activities require the organization of ideas, the generation of hypotheses, the collection of data, and the interpretation, illustration, and analysis of data. No matter where educated people look, this critical analysis is more important than ever in an age where information - and lots of it - is readily available. The average consumer must know what a "median" is or what the connotations of the term "significant" are when intelligently reading The New York Times, Science News, or the Des Moines Register. Likewise, beginning students, practitioners, and researchers must grapple with sophisticated terms and techniques when conducting research, writing proposals, and analyzing data. The terms themselves have proven to be anxiety-provoking.

The *Encyclopedia of Measurement and Statistics* (two volumes, 1100 pages) presents state-of-the-art information and ready-to-use facts from the fields of measurement and statistics in a non-intimidating and accessible style. The encyclopedia is specifically written to appeal to beginning and intermediate-level students, practitioners, researchers, and consumers of information. While there are references that cover statistics and assessment in depth, none provide as comprehensive a resource in as focused and approachable a manner as the proposed encyclopedia. From A to Z, the entries cover every major facet of these two different, but highly integrated disciplines, from mean, mode, and median, to reliability, validity, significance, correlation, and much more - and all without overwhelming the informed reader.

Originally published in print format in 2006.