A conceptual introduction to psychometrics, development, analysis, and application of psychological and educational tests, by G. J. Mellenberg (first edition) – Summary chapter 1

A psychological or educational test is an instrument for the measurement of a person’s maximum or typical performance under standardized conditions, where performance is assumed to reflect one or more latent attributes. Tests are used for diagnosis and psychological and educational decision-making. The dimensionality of a test or subtest is equal to the number of latent attributes which effects test performance. An item is the smallest possible subtest of a test.

A mental test consists of cognitive tasks. A physical test consists of somatic or physiological measurements. A pure power test consists of problems that the test taker tries to solve, without a time-limit. A time-limited power test is a pure power test with a time-limit. A speed test measures the speed taken to solve problems. An ability test (aptitude test) measures a person’s best performance in an area that is not explicitly taught in training and educational programs. An achievement test measures a person’s best performance in an area that is explicitly taught in training and educational programs.