What is the average IQ?

Standardized IQ tests are calibrated that the median performance is always 100.

Based on this definition more, then two thirds of people perform within one deviation, between 85 and 115 IQ point.

These people have average performance.

People with performance between one and two deviations (between 70 and 84 and between 115 and 130 IQ) are located on both side of average performance, and corresponding for 27% of people.

It means that approx. 95% of people can be found within two deviations (between 70 and 130 IQ).

We call these people average in a wider sense.

People with higher than 130 IQ points (about 2,3% of people) are exceptionally intelligent and they can be a member of Mensa International.

These people can be grouped any further based on their distance from the average performance.

So for example we have an IQ tests which consists of 60 tasks

and people at our age can solve 40 tasks correctly on the average

and the standard deviation is 5 points.

So, people solving 40 tasks correctly, have an IQ of 100.

People solving 35 correctly, have an IQ of 85 and finally people solving 50 correctly have an IQ of 130.

So in this case, the IQ is not a quotient as the name suggests, and it is not an absolute number as your height.

It is a relative index expressing the performance of the given person in his country at his age.

One of the basic questions is, if IQ has an important role if your child will be a genius?

Do you have to worry if your child has an IQ of 100? 

Or an IQ of 125?

Or if he was not accepted to a member of Mensa International?

Let’s go deep in this topic in the next lesson.

Előd Szabó
Előd Szabó