THE
QUESTION OF "GENIUS"
A
report from the Supervisory Psychologist
Reprinted from the American Mensa, Ltd Website
American
Mensa is often considered an "expert" source of information on
intelligence and IQ testing. Dr. Abbie Salny, Mensa's supervisory
psychologist, is the organization's spokesperson on these matters. The
following paragraphs are Dr. Salny's answers to some of the most
frequently asked questions as excerpted from a recent article published
in the Mensa Bulletin, Mensa's monthly member publication.
The
History of IQ:
The French
government had commissioned a man named Binet to devise a test that
would enable the school authorities to determine which students
"could but wouldn't" and which "just couldn't."
Thus, the first intelligence test was born. In the 1920s, Lewis Terman
tested hundreds of children in the California public schools. He was a
professor at Stanford University and had worked on the American version
of the Binet test, which became the Stanford-Binet. At the time, tests
were established for each age level. The IQ was determined by dividing
mental age by chronological age, moving the decimal point two places to
the right, and adding one or two zeros as necessary. This was truly a
quotient. However, "IQ" is now a misnomer - the score has been
read from a standardized table for the past 60 years. A percentile rank,
which Mensa uses, is the correct designation.
How can
different tests qualify for Mensa membership?:
For Mensa,
an applicant must achieve a score at the 98th percentile on a
standardized, supervised intelligence test or equivalent. The 98th
percentile is two standard deviations* above the mean (rounded off). The
Stanford-Binet and many school tests have a mean of 100 and a standard
deviation of 16, so Mensa's qualifying score is 132. On the other hand,
the Cattell IIIB and the Raven's Advanced Progressive Matrices (old
form) have a mean of 100 and a standard deviation of 24. Mensa requires
a score of 148 for these tests. The score of 148 represents exactly the
same 98th percentile. An IQ score means nothing without the name of the
test by which it was determined. I read of a woman who said that her son
had an IQ of 178. Actually, he had taken the old Cattell IIIB, and that
178 IQ is equivalent to 152 IQ on the Stanford-Binet.
*Standard
deviation is a mathematically determined figure to account for variances
from the average.
Abbie
F. Salny, Ed.D.
Supervisory Psychologist, American Mensa
Copyright © 2007 Permian Basin Mensa. The Mensa logo is a registered trademark of Mensa International Limited and American Mensa Limited, all rights reserved. Mensa does not hold any opinion or have, or express, any political or religious views.