That's kinda interesting, crazy and funny at the same time: http://en.wikipedia.org/wiki/High_IQ_society. To me it mostly looks like this is to make the members feel somewhat outstanding, making up for their own social deficiencies.
# Top 5% (95th percentile; 1/20; IQ 124 sd15, IQ 126 sd16): International High IQ Society
# Top 2% (98th percentile; 1/50; IQ 130 sd15, IQ 132 sd16): Encefálica Society, High Potentials Society, Mensa International, Mysterium Society
# Top 1% (99th percentile; 1/100; IQ 135 sd15, IQ 137 sd16): Intertel, Top One Percent Society
# Top 0.5% (99.5th percentile; 1/200; IQ 139 sd15, IQ 141 sd16): Colloquy (Society), Poetic Genius Society[2]
# Top 0.37% (99.63rd percentile; 1/270; IQ 140 sd15): Infinity International Society, HispanIQ International Society
# Top 0.3% (99.7th percentile; 3/1,000; IQ 141 sd15, IQ 144 sd16): Cerebrals Society
# Top 0.2% (99.8th percentile; 1/500; IQ 143 sd15, IQ 146 sd16): Exactiq High IQ Society, ePiq
# Top 0.13% (99.87th percentile; 13/10,000; IQ 145 sd15, IQ 148 sd16): CIVIQ Society
# Top 0.1% (99.9th percentile; 1/1,000; IQ 146 sd15, IQ 149 sd16): Glia Society, International High IQ Society Milenija, International Society for Philosophical Enquiry, Iquadrivium Society[2], One-in-a-Thousand Society[2], Triple Nine Society
# Top 0.07% (99.93th percentile; IQ 148 sd15, IQ 151 sd16): ISI-Society
# Top 0.003% (99.997th percentile; 3/100,000; IQ 160 sd15, IQ 164 sd16): Prometheus Society, Tetra Society,Homo Universalis Society
# Top 0.001% (99.999th percentile, 1/100,000; IQ 164 sd15, IQ 168 sd16): Eximia High IQ Society, GenerIQ Society, The Ultranet
# Top 0.00001% (99.9999th percentile,1/1,000,000; IQ 172 sd15, IQ 176 sd16): The Mega Society, The Omega Society
# Top 0.000003% (99.99997th percentile; IQ 175 sd15, IQ 180 sd16): OLYMPIQ Society, PARS Society
Interesting. With the most restrictive category, only 200 people in the world could be admitted. Most people are somewhat skeptical of IQ tests, but does anyone actually think that any test could be accurate enough to pick the 200 most intelligent humans in the world?
any standardized measure claiming to accurately measure beyond 2.5 sds would be a very noisy measure, almost pointlessly so
Yes. Even better than saying "measure" would be to say "estimate of rank order," but indeed it has been well known for a long time that IQ tests have their greatest error of estimation at the high end of the IQ scale. Lewis Terman, the developer of the first widely used school IQ test in the United States, the Stanford-Binet, noted that error of estimation in IQ scores increases as IQ scores are above the mean.
"The reader should not lose sight of the fact that a test with even a high reliability yields scores which have an appreciable probable error. The probable error in terms of mental age is of course larger with older than with young children because of the increasing spread of mental age as we go from younger to older groups. For this reason it has been customary to express the P.E. [probable error] of a Binet score in terms of I.Q., since the spread of Binet I.Q.'s is fairly constant from age to age. However, when our correlation arrays [between Form L and Form M] were plotted for separate age groups they were all discovered to be distinctly fan-shaped. Figure 3 is typical of the arrays at every age level.
"From Figure 3 it becomes clear that the probable error of an I.Q. score is not a constant amount, but a variable which increases as I.Q. increases. It has frequently been noted in the literature that gifted subjects show greater I.Q. fluctuation than do clinical cases with low I.Q.'s . . . . we now see that this trend is inherent in the I.Q. technique itself, and might have been predicted on logical grounds." (Terman & Merrill, 1937, p. 44)
Terman, Lewis & Merrill, Maude (1937). Measuring Intelligence: A Guide to the Administration of the New Revised Stanford-Binet Tests of Intelligence. Boston: Houghton Mifflin.
# Top 5% (95th percentile; 1/20; IQ 124 sd15, IQ 126 sd16): International High IQ Society
# Top 2% (98th percentile; 1/50; IQ 130 sd15, IQ 132 sd16): Encefálica Society, High Potentials Society, Mensa International, Mysterium Society
# Top 1% (99th percentile; 1/100; IQ 135 sd15, IQ 137 sd16): Intertel, Top One Percent Society
# Top 0.5% (99.5th percentile; 1/200; IQ 139 sd15, IQ 141 sd16): Colloquy (Society), Poetic Genius Society[2]
# Top 0.37% (99.63rd percentile; 1/270; IQ 140 sd15): Infinity International Society, HispanIQ International Society
# Top 0.3% (99.7th percentile; 3/1,000; IQ 141 sd15, IQ 144 sd16): Cerebrals Society
# Top 0.2% (99.8th percentile; 1/500; IQ 143 sd15, IQ 146 sd16): Exactiq High IQ Society, ePiq
# Top 0.13% (99.87th percentile; 13/10,000; IQ 145 sd15, IQ 148 sd16): CIVIQ Society
# Top 0.1% (99.9th percentile; 1/1,000; IQ 146 sd15, IQ 149 sd16): Glia Society, International High IQ Society Milenija, International Society for Philosophical Enquiry, Iquadrivium Society[2], One-in-a-Thousand Society[2], Triple Nine Society
# Top 0.07% (99.93th percentile; IQ 148 sd15, IQ 151 sd16): ISI-Society
# Top 0.003% (99.997th percentile; 3/100,000; IQ 160 sd15, IQ 164 sd16): Prometheus Society, Tetra Society,Homo Universalis Society
# Top 0.001% (99.999th percentile, 1/100,000; IQ 164 sd15, IQ 168 sd16): Eximia High IQ Society, GenerIQ Society, The Ultranet
# Top 0.00001% (99.9999th percentile,1/1,000,000; IQ 172 sd15, IQ 176 sd16): The Mega Society, The Omega Society
# Top 0.000003% (99.99997th percentile; IQ 175 sd15, IQ 180 sd16): OLYMPIQ Society, PARS Society
Oh, and http://en.wikipedia.org/wiki/Imperial_examination