Modern Tests
Well-known modern IQ tests include Raven's Progressive Matrices, Wechsler Adult Intelligence Scale, Wechsler Intelligence Scale for Children, Stanford-Binet, Woodcock-Johnson Tests of Cognitive Abilities, and Kaufman Assessment Battery for Children.
Approximately 95% of the population have scores within two standard deviations (SD) of the mean. If one SD is 15 points, as is common in almost all modern tests, then 95% of the population are within a range of 70 to 130, and 98% are below 131. Alternatively, two-thirds of the population have IQ scores within one SD of the mean, i.e. within the range 85-115.
IQ scales are ordinally scaled. While one standard deviation is 15 points, and two SDs are 30 points, and so on, this does not imply that mental ability is linearly related to IQ, such that IQ 50 means half the cognitive ability of IQ 100. In particular, IQ points are not percentage points.
The correlation between IQ test results and achievement test results is about 0.7.
Read more about this topic: Intelligence Quotient
Famous quotes containing the words modern and/or tests:
“He was naturally so sensitive, and so kind. But he had the insidious modern disease of tolerance. He must tolerate everything, even a thing that revolted him.”
—D.H. (David Herbert)
“From a hasty glance through the various tests I figure it out that I would be classified in Group B, indicating “Low Average Ability,” reserved usually for those just learning to speak the English Language and preparing for a career of holding a spike while another man hits it.”
—Robert Benchley (1889–1945)