What IQ score is 2 standard deviations below the mean?

Deviation IQ Scores Further, we would expect that 95% of the distribution lies within 2 standard deviations of the mean (that is IQs between 70 and 130). Thus, scores that fall above 130 and below 70 would be considered unusually high and unusually low, as only 5% of the population obtains higher or lower scores.

What are the standard deviations for IQ?

The mean, or average, IQ is 100. Standard deviations, in most cases, are 15 points. The majority of the population, 68.26%, falls within one standard deviation of the mean (IQ 85-115).

How is standard deviation used in IQ testing?

A standard deviation is a measure of the spread of the distribution – the bigger the standard deviation, the more spread out the scores in the population. 15 points is one standard deviation for most IQ tests. Nearly 70% of the population score between 85 and 115 – i.e. plus and minus one standard deviation.

Is 2.5 A high IQ?

Typically, an IQ score of 130 is used as the limit. 2.5% of the population achieves an IQ test score that high. According to this definition, there would be 125 million highly gifted people in a world population of five billion.

What does 2 standard deviation mean?

“Within two standard deviations” means two standard deviations below the mean and two standard deviations above the mean. In this case, the mean is 64 years, and the standard deviation is 3.5 years. So two standard deviations is (3.5)(2) = 7 years.

What is the IQ scale?

IQ stands for “Intelligence Quotient” and is a measure of human intelligence obtained through standardized tests. The IQ scale is defined such that most people have an IQ between 80 and 120 (see below on interpreting your IQ score).

What are IQ numbers?

IQ is a number meant to measure people cognitive abilities (intelligence) in relation to their age group. An I.Q between 90 and 110 is considered average; over 120, superior.

What is the definition of deviation?

Definition of deviation : an act or instance of deviating: such as : an action, behavior, or condition that is different from what is usual or expected technical : the difference between the average of a group of numbers and a particular number in that group : an act or instance of diverging from an established way or in a new direction: as