In 1905, French psychologists designed the world's first intelligence test. These tests, each with 30 questions, test people's ability of judgment, understanding and logic. This set of tests was adopted by the French government at that time to test the intelligence of students, so as to find out those with lower intelligence and provide special education services for them. After that, the previous designed test was revised continuously to get a concept of intelligence age.
Intelligence quotient and intelligence age
Mental age refers to the average level of intelligence that children of a certain age group can achieve. For example, the performance of a 10-year-old child in intelligence test is as good as that of an ordinary 10-year-old child. Let's say that the child's intelligence age is 10 years old, although his actual age is only 8 years old.
In 1916, psychologist stern put forward the concept of intelligence quotient: if a child's intelligence age is the same as his physiological age, then his intelligence is average; but if his intelligence age is higher or lower than his physiological age, then his intelligence is higher or lower than the average level.
IQ (I.Q.) = (intelligence age / physiological age) & times; 100%
For example, in the above example, the child's intelligence age is 10, and his physiological age is 8, so his IQ = (10 & divide; 8) & times; 100 = 125.
Intelligence quotient (I.Q.) intelligence level
More than 140 or close to genius
120-140 excellent intelligence
110-120 have higher intelligence
90-110 general intelligence
The 80-90 retarded couple is of low energy
70-80 between dull and low energy (each can be classified as low energy)
Low energy is defined below 70
According to statistics, about 50% of the population has an IQ between 90 and 110, that is, about 25% of the population has an IQ less than 90 (by definition, an IQ of 100 is the average intelligence level of the population). Those with IQ between 110 and 120 account for about 14.5% of the population; those with IQ between 120 and 130 account for about 7%, those with IQ between 130 and 140 account for about 3%, and those with IQ over 140 account for only 0.5% of the population.
On the low intelligence side, there is a similar distribution. For example, the IQ between 70 and 80, there are 7% and so on.
It can be seen that there are very few people who are 'gifted' or 'retarded', and most of them are of general intelligence.
There are many ways to measure intelligence, such as observation, experiment, conversation, case investigation, work analysis, intelligence test, etc.