Psychological testing is a field characterized by the use of small samples of behavior in order to infer larger generalizations about a given individual. The technical term for psychological testing is
psychometrics. By samples of behavior, we mean observations of the individual over a limited amount of time performing tasks which have usually been prescribed beforehand, often with a great deal of research into the responses of members of a
norm group[?]. These responses are often compiled into statistical tables that allow the evaluator to compare the behavior of the individual being tested to the responses of the range of responses given by people in the norm group.
IQ tests and
academic achievement[?] tests are the most familiar norm-referenced tests for most people. In either of these types of tests, a series of tasks are presented to the person being evaluated, and the person's responses are graded according to carefully prescribed guidelines. After the test is completed, the results can be compiled and compared to the responses of a norm group usually composed of people at the same age or grade level as the person being evaluated.
IQ tests and academic achievement tests are designed to be administered to either an individual (by a trained evaluator) or to a group of people (paper and pencil tests). The individually-administered tests tend to be more comprehensive, more reliable[?], more valid[?] and generally to have better psychometric characteristics than group-administered tests. Of course, individually-administered tests are more expensive to administer because of the need for a trained administrator (psychologist, school psychologist[?], or psychometrician[?]), and the limitation of working with just one person.