High IQ society
A high IQ society is an organization that limits its membership to people who have attained a specified score on an IQ test. The oldest and best-known such society is Mensa International, which was founded by Roland Berrill and Lancelot Ware in 1946. Other societies are Intertel, founded by Ralph Haines in 1966; the Triple Nine Society, founded in 1978; the Prometheus Society; and the Mega Society.
High IQ societies typically accept a variety of IQ tests for membership eligibility; these include WAIS, Stanford-Binet, and Raven's Advanced Progressive Matrices, amongst many others deemed to sufficiently measure or correlate with intelligence. Tests deemed to insufficiently correlate with intelligence (e.g. post-1994 SAT, in the case of Mensa and Intertel) are not accepted for admission . As IQ significantly above 146 SD15 (approximately three-sigma) cannot be reliably measured with accuracy due to sub-test limitations and insufficient norming, IQ societies with cutoffs significantly higher than three-sigma should be considered dubious.
Some societies, including widely known societies such as Mensa, accept the results of standardized tests taken elsewhere. Those are listed below by selectivity percentile (assuming the now-standard definition of IQ as a standard score with a median of 100 and a standard deviation of 15 IQ points):
- Mensa International – as of May 2017, ~134,000 members from ~100 countries; current annual dues as of November 2017 for American Mensa are $79 (dues differ by country); Life membership cost varies by age.
Top 2 percent of population (98th percentile; 1 person out of 50; approximately IQ 130):
- Intertel – as of January 2014, 1,300-1,400 members; annual dues are $39
Top 1 percent (99th percentile; 1 out of 100; approximately IQ 135):
- Triple Nine Society – as of November 2017, 1,800+ members from 46 countries; annual dues are $10; Life membership is $183.
Top 0.1 percent (99.9th percentile; 1 out of 1,000; approximately IQ 146):
- Prometheus Society – as of January 2014, ~120 members; annual dues are $10.
Top 0.003 percent (99.997th percentile; 1 out of 30,000; approximately IQ 160) (not reliable with current tests):
- Mega Society – as of January 2014, 26 members
Top 0.0001 percent (99.9999th percentile; 1 out of 1,000,000; approximately IQ 172)
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