PSYC1023 Lecture Notes - Lecture 3: Twin, Flynn Effect, Wechsler Adult Intelligence Scale
Document Summary
David wechsler invented wais in 1939 and the wisc in 1949. Wisc: wechsler intelligence scale for children 1949. The tests included nonverbal questions like assembling pieces of a puzzle. All paper and pencil tests require reading and writing skills, so they are measuring more verbal ability but not general intelligence. The tests also introduce the concept of normal distribution (bell curve) Iq = ma/ca x 100, ma: mental age and ca: chronological age. Ex: jill is 10 years old & does as well on an iq test as the average 10 year old. About 68% of the population have an iq score between 85-115. About 2% have an iq score >130 (gifted) and <70 (retardation) Today iq scores are based on a normal distribution (deviation iq scores) Validity correlations = 0. 7 for years of school and 0. 3 for job success. Iq scores do not predict: happiness, financial income and occupation etc. The predict school performance like what binet wanted.
