Intelligence test

IQ tests are designed to give approximately this Gaussian distribution. Colors delineate one standard deviation. But the true frequency of low and high IQs is greater than that given by the Gaussian curve.

An intelligence quotient or IQ is a score derived from a set of standardized tests of intelligence. Intelligence tests come in many forms. Most tests yield both an overall score and individual subtests scores. Regardless of design, all IQ tests measure the same general intelligence. Component tests are generally designed and chosen because they are found to be predictable of later intellectual development and educational achievement. IQ also correlates with job performance, socioeconomic advancement, and "social pathologies". Recent work has demonstrated links between IQ and health, longevity, and functional literacy. However, IQ tests do not measure potential. IQ scores are relative and aren't absolutely accurate.

History

In 1905, the French psychologist Alfred Binet published the first modern intelligence test, the Binet-Simon intelligence scale. His principal goal was to identify students who needed special help in coping with the school curriculum. Along with his collaborator Theodore Simon, Binet published revisions of his intelligence scale in 1908 and 1911, the last appearing just before his untimely death. In 1912, the abbreviation of "intelligence quotient" or I.Q., a translation of the German Intelligenz-quotient, was coined by the German psychologist William Stern.

A further refinement of the Binet-Simon scale was published in 1916 by Lewis M. Terman, from Stanford University, who incorporated Stern's proposal that an individual's intelligence level be measured as an intelligence quotient (I.Q.). Terman's test, which he named the Stanford-Binet Intelligence Scale formed the basis of one of the modern intelligence tests still commonly used today. They are all colloquially known as IQ tests.

IQ and general intelligence factor

Modern IQ tests produce scores for different areas (e.g., language fluency, three-dimensional thinking, etc.), with a summary score calculated from subtest scores. Individual subtest scores tend to correlate with one another, even when seemingly disparate in content.

Analyses of individuals' scores on the subtests of a single IQ test or the scores from a variety of different IQ tests (e.g., Stanford-Binet, WISC-R, Raven's Progressive Matrices Universal Nonverbal Intellience Test, and others) reveal that they all measure a single common factor and various factors that are specific to each test. This kind of factor analysis has led to the theory that underlying these disparate cognitive tasks is a single factor, termed the general intelligence factor (or g), that corresponds with the common-sense concept of intelligence. In the normal population, g and IQ are roughly 90% correlated and are often used interchangeably.

Practical validity

Evidence for the practical validity of IQ comes from examining the correlation between IQ scores and life outcomes.

Economic and social correlates of IQ

Factors	Correlation
School grades and IQ	0.5
Total years of education and IQ	0.55
IQ and parental socioeconomic status	0.33
Job performance and IQ	0.54
Negative social outcomes and IQ	−0.2
IQs of identical twins	0.86
IQs of husband and wife	0.4
Heights of parent and child	0.47

Economic and social correlates of IQ in the USA

IQ	<75	75–90	90–110	110–125	>125
US population distribution	5	20	50	20	5
Married by age 30	72	81	81	72	67
Out of labor force more than 1 month out of year (men)	22	19	15	14	10
Unemployed more than 1 month out of year (men)	12	10	7	7	2
Divorced in 5 years	21	22	23	15	9
% of children w/ IQ in bottom decile (mothers)	39	17	6	7	< 1
Had an illegitimate baby (mothers)	32	17	8	4	2
Lives in poverty	30	16	6	3	2
Ever incarcerated (men)	7	7	3	1	< 1
Chronic welfare recipient (mothers)	31	17	8	2	< 1
High school dropout	55	35	6	0.4	< 0.4
Values are the percentage of each IQ sub-population, among non-Hispanic whites only, fitting each descriptor. Compiled by Gottfredson (1997) from a US study by Herrnstein & Murray (1994) pp. 171, 158, 163, 174, 230, 180, 132, 194, 247–248, 194, 146 respectively.

Research shows that general intelligence plays an important role in many valued life outcomes. IQ correlates with academic success, job performance (see below), socioeconomic advancement (e.g., level of education, occupation, and income), and "social pathology" (e.g., adult criminality, poverty, unemployment, dependence on welfare, children outside of marriage). Recent work has demonstrated links between general intelligence and health, longevity, and functional literacy. Correlations between g and life outcomes are pervasive, though IQ and happiness do not correlate. IQ and g correlate highly with school performance and job performance, less so with occupational prestige, moderately with income, and to a small degree with citizenship.

However, legal barriers, most prominently the US Civil Rights Act, as interpreted in the 1971 United States Supreme Court decision Griggs v. Duke Power Co., have prevented American employers from using cognitive ability tests as a controlling factor in selecting employees where (1) the use of the test would have a disparate impact on hiring by race and (2) where the test is not shown to be directly relevant to the job or class of jobs at issue. Instead, where there is not direct relevance to the job or class of jobs at issue, tests have only been legally permitted to be used in conjunction with a subjective appraisal process. The U.S. military uses the Armed Forces Qualifying Test (AFQT), as higher scores correlate with significant increases in effectiveness of both individual soldiers and units,[1] [2] and Microsoft is known for using non-illegal tests that correlate with IQ tests as part of the interview process, weighing the results even more than experience in many cases.[3] [4]

Some researchers have echoed the popular claim that "in economic terms it appears that the IQ score measures something with decreasing marginal value. It is important to have enough of it, but having lots and lots does not buy you that much." (Detterman and Daniel, 1989)[5]

Some studies continue to suggest that one's IQ continues to confer large benefits even at very high levels. Ability and performance for jobs are linearly related, such that at all IQ levels, an increase in IQ translates into a concomitant increase in performance (Coward and Sackett, 1990). In an analysis of hundreds of siblings, it was found that IQ has a substantial effect on income independently of family background (Murray, 1998).

Other studies question the real-world importance of whatever is measured with IQ tests, especially for differences in accumulated wealth and general economic inequality in a nation. IQ correlates highly with school performance but the correlations decrease the closer one gets to real-world outcomes, like with job performance, and still lower with income. It explains less than one sixth of the income variance [6]. Even for school grades, other factors explain most the variance. One study found that, controlling for IQ across the entire population, 90 to 95 percent of economic inequality would continue to exist. [7]. Another recent study (2002) found that wealth, race, and schooling are important to the inheritance of economic status, but IQ is not a major contributor and the genetic transmission of IQ is even less important [8]. Some argue that IQ scores are used as an excuse for not trying to reduce poverty or otherwise improve living standards for all. Claimed low intelligence has historically been used to justify the feudal system and unequal treatment of women (but note that many studies find identical average IQs among men and women; see sex and intelligence). In contrast, others claim that the refusal of high-IQ elites to take IQ seriously as a cause of inequality is itself immoral.[9]

The Flynn effect

Worldwide, IQ scores appear to be slowly rising, a trend known as the Flynn effect. Flynn, 1999. The Flynn effect has been observed to be so severe that it is difficult to explain. However, tests are only renormalized occasionally to obtain mean scores of 100, for example WISC-R (1974), WISC-III (1991) and WISC-IV (2003). Hence it is difficult to compare IQ scores measured years apart.

Genetics versus environment

The role of genes and environment (nature vs. nurture) in relation to IQ is reviewed in Plomin et al. (2001, 2003). The degree to which genetic variation contributes to observed variation in a trait is measured by a statistic called heritability. Heritability scores range from 0 to 1, and can be interpreted as the percentage of variation (e.g. in IQ) that is due to variation in genes. Twins studies are commonly used to determine the heritability of a trait. Until recently heritability was mostly studied in children. These studies find the heritability of IQ is approximately 0.5; that is, half of the variation in IQ among the children studied was due to variation in their genes. The remaining half was thus due to environmental variation and measurement error. A heritability of 0.5 implies that IQ is "substantially" heritable. Studies with adults show that they have a higher heritability of IQ than children do and that heritability could be as high as 0.8. The American Psychological Association's 1995 task force on "Intelligence: Knowns and Unknowns" concluded that within the White population the heritability of IQ is "around .75" (p. 85).[10]

Environment

Environmental factors play a large role in determining IQ in extreme situations. Proper childhood nutrition appears critical for cognitive development; malnutrition can lower IQ. Other research indicates environmental factors such as prenatal exposure to toxins, duration of breastfeeding, and micronutrient deficiency can affect IQ. In the developed world, there are some family effects on the IQ of children, accounting for up to a quarter of the variance. However, by adulthood, this correlation disappears, so that the IQ of adults living in the prevailing conditions of the developed world may be more heritable.

Nearly all personality traits show that, contrary to expectations, environmental effects actually cause adoptive siblings raised in the same family to be as different as children raised in different families (Harris, 1998; Plomin & Daniels, 1987). Put another way, shared environmental variation for personality is zero, and all environmental effects would be nonshared. Conversely, IQ is actually an exception to this, at least among children. The IQs of adoptive siblings, who share no genetic relation but do share a common family environment, are correlated at .32. Despite attempts to isolate them, the factors that cause adoptive siblings to be similar have not been identified. However, as explained below, shared family effects on IQ disappear after adolescence.

Active genotype-environment correlation, also called the "nature of nurture", is observed for IQ. This phenomenon is measured similarly to heritability; but instead of measuring variation in IQ due to genes, variation in environment due to genes is determined. One study found that 40% of variation in measures of home environment are accounted for by genetic variation. This suggests that the way human beings craft their environment is due in part to genetic influences.

A study of French children adopted between the ages of 4 and 6 shows the continuing interplay of nature and nurture. The children came from poor backgrounds with I.Q.’s that initially averaged 77, putting them near retardation. Nine years later after adoption, they retook the I.Q. tests, and all of them did better. The amount they improved was directly related to the adopting family’s status. "Children adopted by farmers and laborers had average I.Q. scores of 85.5; those placed with middle-class families had average scores of 92. The average I.Q. scores of youngsters placed in well-to-do homes climbed more than 20 points, to 98."[11] This study suuggests that IQ is not stable over the course of ones lifetime and that, even in later childhood, a change in enviornment can have a significant effect on IQ.

Development

It is reasonable to expect that genetic influences on traits like IQ should become less important as one gains experiences with age. Surprisingly, the opposite occurs. Heritability measures in infancy are as low as 20%, around 40% in middle childhood, and as high as 80% in adulthood.

Shared family effects also seem to disappear by adulthood. Adoption studies show that, after adolescence, adopted siblings are no more similar in IQ than strangers (IQ correlation near zero), while full siblings show an IQ correlation of 0.6. Twin studies reinforce this pattern: monozygotic (identical) twins raised separately are highly similar in IQ (0.86), more so than dizygotic (fraternal) twins raised together (0.6) and much more than adopted siblings (~0.0).

Most of the IQ studies described above were conducted in developed countries, such as the United States, Japan, and Western Europe. Also, a few studies have been conducted in Moscow, East Germany, and India, and those studies produce similar results. Any such investigation is limited to describing the genetic and environmental variation found within the populations studied. This is a caveat of any heritability study.^{[citation needed]}

IQ, education, and income

Tambs et al. (1989) found that occupational status, educational attainment, and IQ are individually heritable; and further found that "genetic variance influencing educational attainment … contributed approximately one-fourth of the genetic variance for occupational status and nearly half the genetic variance for IQ". In a sample of US siblings, Rowe et al. (1997) report that the inequality in education and income was predominantly due to genes, with shared environmental factors playing a subordinate role.

IQ correlations

Race and IQ

While IQ scores of individual members of different racial or ethnic groups are widely distributed across the IQ scale, as a whole, the groups vary in where their averages. Ashkenazi Jews and East Asians cluster higher than Europeans, while Hispanics and Sub-Saharan Africans cluster lower. Much research has been devoted to the extent and potential causes of racial-ethnic group differences in IQ, eaximing the underlying purposes and validity of intelligence tests. Most experts conclude that examination of many types of test bias and differences in socioeconomic status have failed to explain the IQ clustering differences.

The findings in this field are often thought to conflict with fundamental social philosophies, and have ignited large controversy.<ref> Some scientists to debate whether or not some areas of research are inappropriate.

Religious Belief and IQ

Several studies have investigated the relationship between intelligence and the degree of religious belief (excluding humanism), with most showing that intelligence averages decrease significantly with the "importance of religion" (as indicated by the IQ testee). Many studies chiefly show the same results (despite time of study, location, etc.). Charles Murray, author of The Bell Curve, chronicled the attitudes and beliefs of the Elites (elite in regards to I.Q.) in regards to religion spanning from Ancient times to the Modern Day and across the globe in his book, Human Accomplishment. He wrote that Elites in the First World, post-1950 were wary of religion.

Health and IQ

Persons with a higher IQ have generally lower adult morbidity and mortality. This may be because they are better at avoiding injury and taking better care of their health. This may be due to a slight increased propensity for material wealth. Post-Traumatic Stress Disorder, severe depression, and schizophrenia are less prevalent in higher IQ bands since these disorders greatly affect participant's concentration and may affect the test taking itself. On the other hand, higher IQ scores correlate a higher prevalence of those suffering from Obsessive Compulsive Disorder [12].

Research in Scotland has shown that a 15-point lower IQ meant people had a 20% less chance of seeing their 76th birthday, while those with a 30-point disadvantage were 37% less likely than those with a higher IQ to live that long [13].

Economic development and IQ

A controversial book IQ and the Wealth of Nations, claims to show that the wealth of a nation can in large part be explained by the average IQ score. The data which supports this claim has been both disputed and supported in peer-reviewed papers.

Public policy

Because public policy is often intended to influence the same outcomes (for example to improve education, fight poverty and crime, promote fairness in employment, and counter racial discrimination), policy decisions frequently interact with intelligence measures. In some cases, modern public policy references intelligence measures or even aims to alter cognitive development directly.

While broad consensus exists that intelligence measures neither dictate nor preclude any particular social policy, controversy surrounds many other aspects of this interaction. Central issues concern whether intelligence measures should be considered in policy decisions, the role of policy in influencing or accounting for group differences in measured intelligence, and the success of policies in light of individual and group intelligence differences. The importance and sensitivity of the policies at issue have produced an often-emotional ongoing debate spanning scholarly inquiry and the popular media from the national to the local level.

Use of IQ in the United States legal system

Title VI of the Civil Rights Act generally prohibits employment practices that are unfair or discriminatory. One provision of Title VI, 42 USC 2000(e)(2)(h), specifically provides that it is not an "unlawful employment practice for an employer to give and to act upon the results of any professionally developed ability test provided that such test, its administration or action upon the results is not designed, intended or used to discriminate because of race, color, religion, sex or national origin." This statute was interpreted by the Supreme Court in Griggs v. Duke Power Co., 401 US 424 (1971). In Griggs, the Court ruled that the reliance solely on a general IQ test that was not found to be specifically relevant to the job at issue was a discriminatory practice where it had a "disparate impact" on hiring. The Court gave considerable weight in its ruling to an Equal Employment Opportunity Commission regulation interpreting Section 2002(e)(2)(h)'s reference to a "professionally developed ability test" to mean "a test which fairly measures the knowledge or skills required by the particular job or class of jobs which the applicant seeks, or which fairly affords the employer a chance to measure the applicant's ability to perform a particular job or class of jobs." In other words, the use of any particular test would need to be shown to be relevant to the particular job or class of jobs at issue.

In the educational context, the 9th Circuit Court of Appeals interpreted similar state and federal statutes to require that IQ Tests not be used in a manner that was determinative of tracking students into classes designed for the mentally retarded. Larry P. v. Riles, 793 F.2d 969 (9th Cir. 1984). The court specifically found that the tests involved were designed and standardized based on an all-white population, and had not undergone a legislatively mandated validation process. In addition, the court ruled that predictive validity for a general population is not sufficient, since the rights of an individual student were at issue, and emphasized that had the tests not been treated as controlling but instead used as part of a thorough and individualized assessment by a school psychologist a different result would have obtained.

The Supreme Court of the United States has utilized IQ test results during the sentencing phase of some criminal proceedings. The Supreme Court case of Atkins v. Virginia, decided June 20 2002, [14] held that executions of mentally retarded criminals are "cruel and unusual punishments" prohibited by the Eighth Amendment. In Atkins the court stated that

"…[I]t appears that even among those States that regularly execute offenders and that have no prohibition with regard to the mentally retarded, only five have executed offenders possessing a known IQ less than 70 since we decided Penry. The practice, therefore, has become truly unusual, and it is fair to say that a national consensus has developed against it."

In overturning the Virginia Supreme Court's holding, the Atkins opinion stated that petitioner's IQ result of 59 was a factor making the imposition of capital punishment a violation of his eighth amendment rights. In the opinion's notes the court provided some of the facts relied upon when reaching their decision

"At the sentencing phase, Dr. Nelson testified: "Atkins' full scale IQ is 59. Compared to the population at large, that means less than one percentile…. Mental retardation is a relatively rare thing. It's about one percent of the population." App. 274. According to Dr. Nelson, Atkins' IQ score "would automatically qualify for Social Security disability income." Id., at 280. Dr. Nelson also indicated that of the over 40 capital defendants that he had evaluated, Atkins was only the second individual who met the criteria for mental retardation. Id., at 310. He testified that, in his opinion, Atkins' limited intellect had been a consistent feature throughout his life, and that his IQ score of 59 is not an "aberration, malingered result, or invalid test score." Id., at 308."

Validity and g-loading of specific tests

While IQ is sometimes treated as an end unto itself, scholarly work on IQ focuses to a large extent on IQ's validity, that is, the degree to which IQ predicts outcomes such as job performance, social pathologies, or academic achievement. Different IQ tests differ in their validity for various outcomes.

Tests also differ in their g-loading, which is the degree to which the test score reflects general mental ability rather than a specific skill or "group factor" such as verbal ability, spatial visualization, or mathematical reasoning). g-loading and validity have been observed to be related in the sense that most IQ tests derive their validity mostly or entirely from the degree to which they measure g (Jensen 1998).

Social construct

Some maintain that IQ is a social construct invented by the privileged classes, used to maintain their privilege. Others maintain that intelligence, measured by IQ or g, reflects a real ability, is a useful tool in performing life tasks and has a biological reality.

The social-construct and real-ability interpretations for IQ differences can be distinguished because they make opposite predictions about what would happen if people were given equal opportunities. The social explanation predicts that equal treatment will eliminate differences, while the real-ability explanation predicts that equal treatment will accentuate differences. Evidence for both outcomes exists. Achievement gaps persist in socioeconomically advantaged, integrated, liberal, suburban school districts in the United States (see Noguera, 2001). Test-score gaps tend to be larger at higher socioeconomic levels (Gottfredson, 2003). Some studies have reported a narrowing of score gaps over time.

The reduction of intelligence to a single score seems extreme and unrealistic to many people. Opponents argue that it is much more useful to know a person's strengths and weaknesses than to know their IQ score. Such opponents often cite the example of two people with the same overall IQ score but very different ability profiles. As measured by IQ tests, most people have highly balanced ability profiles, with differences in subscores being greater among the more intelligent. However, this assumes the ability of IQ tests to comprehensively gauge the wide variety of human intellectual abilities.

The creators of IQ testing did not intend for the tests to gauge a person's worth, and in many (or, as some people suggest, all) situations, IQ may have little relevance.

The view of the American Psychological Association

In response to the controversy surrounding The Bell Curve, the American Psychological Association's Board of Scientific Affairs established a task force to write a consensus statement on the state of intelligence research which could be used by all sides as a basis for discussion. The full text of the report is available at a third-party website. [15]

The findings of the task force state that IQ scores do have high predictive validity for individual (but not necessarily population) differences in school achievement. They confirm the predictive validity of IQ for adult occupational status, even when variables such as education and family background have been statistically controlled. They agree that individual (again, not necessarily population) differences in intelligence are substantially influenced by genetics.

They state there is little evidence to show that childhood diet influences intelligence except in cases of severe malnutrition. They agree that there are no significant differences between the average IQ scores of males and females. The task force agrees that large differences do exist between the average IQ scores of blacks and whites, and that these differences cannot be attributed to biases in test construction. While they admit there is no empirical evidence supporting it, the APA task force suggests that explanations based on social status and cultural differences may be possible. Regarding genetic causes, they noted that there is not much direct evidence on this point, but what little there is fails to support the genetic hypothesis.

The APA journal that published the statement, American Psychologist, subsequently published eleven critical responses in January 1997, most arguing that the report failed to examine adequately the evidence for partly-genetic explanations.

The report was published in 1995 and thus does not include a decade of recent research.

IQ in the media

A number of television programmes have featured people with high IQ. Many quiz games need an above-average level of intelligence to enter and compete. One of the most interesting combinations was seen on the TV show Top Gear, where high-IQ individuals were asked to interact with a high-powered car.

• Video clip at YouTube

Controversy

The controversy over intelligence quotient (IQ) tests (also called cognitive ability tests), what they measure, and what this means for society has not abated since their initial development by Alfred Binet.

IQ tests rely largely upon Symbolic Logic (etc.) as a means to scoring, and as Symbolic Logic is not inherently synonymous with intelligence, the question remains as to exactly what is being measured via such tests. For instance, it is feasible that someone could possess a prodigious wealth of emotional intelligence while being simultaneously unable to comprehend the significance of sequentially arranged shapes. Additionally, someone who cannot read would be at a significant disadvantage on an IQ test, though illiteracy is not indicative of unintelligence. Measurements of other forms of "intelligence" have been proposed to augment the current IQ Testing Methodology, though such alternative measurements may also be a subject of debate.

Some key issues in the debate include defining intelligence itself (see general intelligence factor) and the political ramification of findings.

Some proponents of IQ testing argue that lower scores by certain groups justify cutting back on welfare and programs like Head Start and New Deal. Many proponents believe different IQ scores demonstrate that power and wealth will always be distributed unequally. Critics claim that IQ tests do not measure intelligence, but rather a specific skill set valued by those who create IQ tests.

Various statistical studies have reported that income level, education level, nutrition level, race, and sex all correlate with IQ scores, but what this means is debated.

Some researchers have concluded from twin studies and adoption studies that IQ has high heritability, and this is often interpreted by the general public as meaning that there is an immutable genetic factor affecting or determining intelligence. This hereditarian interpretation fuels much of the controversy over books such as The Bell Curve, which claimed that various racial groups have lower or higher group intelligence than other racial and ethnic groups (East Asians and Ashkenazi Jews, according to The Bell Curve, are slightly more intelligent than generic whites, whereas blacks have slightly lower IQs) and suggested changing public policy as a result of these findings.

The degree to which nature versus nurture influences the development of human traits (especially intelligence) is one of the most intractable scholarly controversies of modern times.

End material

References

ISBN links support NWE through referral fees

• Carroll, J.B. (1993). Human cognitive abilities: A survey of factor-analytical studies. New York: Cambridge University Press.
• Coward, W.M. and Sackett, P.R. (1990). Linearity of ability-performance relationships: A reconfirmation. Journal of Applied Psychology, 75:297–300.
• Duncan, J., P. Burgess, and H. Emslie (1995) Fluid intelligence after frontal lobe lesions. Neuropsychologia, 33(3): p. 261-8.
• Duncan, J., et al., A neural basis for general intelligence. Science, 2000. 289(5478): p. 457-60.
• Flynn, J.R. (1999). Searching for Justice: The discovery of IQ gains over time. American Psychologist, v. 54, p. 5-20
• Frey, M.C. and Detterman, D.K. (2003) Scholastic Assessment or g? The Relationship Between the Scholastic Assessment Test and General Cognitive Ability. Psychological Science, 15(6):373–378. PDF
• Gottfredson, L. S. (1997). "Why g matters: The complexity of everyday life." Intelligence, 24(1), 79–132. PDF
• Gottfredson, L.S. (1998). The general intelligence factor. Scientific American Presents, 9(4):24–29. PDF
• Gottfredson, L. S. (2005). Suppressing intelligence research: Hurting those we intend to help. In R. H. Wright & N. A. Cummings (Eds.), Destructive trends in mental health: The well-intentioned path to harm (pp. 155–186). New York: Taylor and Francis. Pre-print PDF PDF
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• Murray, Charles (1998). Income Inequality and IQ, AEI Press PDF
• Noguera, P.A. (2001). Racial politics and the elusive quest for excellence and equity in education. In Motion Magazine article
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• Rowe, D. C., W. J. Vesterdal, and J. L. Rodgers, "The Bell Curve Revisited: How Genes and Shared Environment Mediate IQ-SES Associations," University of Arizona, 1997
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External links

Collective statements

• The Wall Street Journal: Mainstream Science on IntelligencePDF Reprint - Mainstream science on intelligence: An editorial with 52 signatories, history, and bibliography.
• APA — Intelligence: Knowns and Unknowns
• APA Committee on Online Psychological Tests and Assessment report

Review papers

• Scientific American: The General Intelligence Factor
• Scientific American: Intelligence Considered
• Neurobiology of Intelligence: Science and Ethics PDF

IQ testing

• "Scans Show Different Growth for Intelligent Brains", New York Times, March 30, 2006
• IQ comparison site
• IQ comparison chart
• Estimated IQs of the greatest geniuses (note: these sorts of estimates are considered highly suspect; the psychological community generally regards it impossible to infer an "IQ" from writing samples or accomplishments)

Online IQ tests

• Kids IQ Test Center Free information regarding childrens intelligence.
• Online IQ Test An online IQ test (40 questions, ~ 40 minutes)
• Online Intelligence Testing IQ Test (clever method of disabusing notions about online IQ tests)

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