Intelligence trait: Encyclopedia II - Intelligence trait - Psychometric intelligence

Intelligence trait - Psychometric intelligence

Main articles: IQ, General intelligence factor

Despite the variety of concepts of intelligence, the most influential approach to understanding intelligence (i.e., the one that has generated the most systematic research) is based on psychometric testing.

Intelligence, narrowly defined, can be measured by intelligence tests, also called IQ (intelligence quotient) tests. Such tests are among the most accurate (reliable and valid) psychological tests. Such intelligence tests take many forms, but the common tests (Stanford-Binet, Raven's Progressive Matrices, Wechsler Adult Intelligence Scale, Wechsler-Bellevue I, and others) all measure the same dominant form of intelligence, g or "general intelligence factor". The abstraction of g stems from the observation that scores on all forms of cognitive tests correlate positively with one another. g can be derived as the principle factor from cognitive test scores using the method of factor analysis.

In the psychometric view, the concept of intelligence is most closely identified with g, or Gf ("fluid g"). However, psychometricians can measure a wide range of abilities, which are distinct yet correlated. One common view is that these abilities are hierarchically arranged with g at the vertex (or top, overlaying all other cognitive abilities).

Intelligence trait - Intelligence IQ and g

Intelligence, IQ, and g are distinct. Intelligence is the term used in ordinary discourse to refer to cognitive ability. However, it is generally regarded as too imprecise to be useful for a scientific treatment of the subject. The intelligence quotient (IQ) is an index calculated from the scores on test items judged by experts to encompass the abilities covered by the term intelligence. IQ measures a multidimensional quantity: it is an amalgam of different kinds of abilities, the proportions of which may differ between IQ tests. The dimensionality of IQ scores can be studied by factor analysis, which reveals a single dominant factor underlying the scores on all IQ tests. This factor, which is a hypothetical construct, is called g. Variation in g corresponds closely to the intuitive notion of intelligence, and thus g is sometimes called general cognitive ability or general intelligence.

Intelligence trait - Criticisms of the psychometric approach

Theorists critical of the psychometric approach, such as Robert Sternberg, point out that people in the general population have a somewhat different conception of intelligence than most experts. In turn, they argue that the psychometric approach measures only a part of what is commonly understood as intelligence. Scholars who believe that intelligence tests accruately measure intelligence argue that lack of agreement over the defintion of intelligence does not itself invalidate the measure. They argue that many scientific concepts were accurately measured before it was understood what was actually being measured (e.g., gravity, temperature, and radiation).

Adapted from the Wikipedia article "Psychometric intelligence", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki