What is a normal iq score
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Understanding Normal IQ Scores
Definition and Standardization of IQ Scores
IQ, or Intelligence Quotient, is a measure used to assess human intelligence. The standardization of IQ scores typically follows a normal distribution with a mean (average) score of 100 and a standard deviation of 15. This means that most people (about 68%) score within one standard deviation of the mean, i.e., between 85 and 115.
Historical Trends in IQ Scores
Research has shown that the average IQ score has increased over time. A study examining IQ scores from 1932 to 1978 found that the mean IQ of Americans rose by 13.8 points over this period. This phenomenon, known as the Flynn effect, suggests that successive generations perform better on IQ tests than previous ones.
IQ Scores in Specific Populations
While the general population's average IQ score is around 100, certain subgroups may have different average scores. For instance, studies on learning disability samples indicate that their average IQ scores are significantly below 100, though still above the threshold for mental retardation. This variation can be explained by the relationship between achievement and IQ, where higher correlations between these factors can result in lower average IQ scores for these groups.
Influence of Education and Occupation on IQ Scores
Educational attainment and occupational specialization also influence IQ scores. Individuals with higher levels of education, such as post-secondary and university education, tend to have higher IQ scores compared to those with only elementary or secondary education. Similarly, occupations requiring advanced tasks, leadership, and administration are associated with higher IQ scores compared to jobs involving practical skills, communication, and practical work.
Conclusion
In summary, a normal IQ score is standardized to have a mean of 100 with a standard deviation of 15. Historical data shows an increase in average IQ scores over time, and specific populations, such as those with learning disabilities, may have lower average scores. Education and occupation also play significant roles in influencing IQ scores, with higher education and specialized occupations correlating with higher IQ levels.
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