题目内容
‘I. Q.' stands for Intelligence Quotient which is a measure of a person's intelligence found by means of an intelligence test. Before marks gained in such a test can be useful as information about a person, they must be compared with some standard, or norm. It is not enough simply to know that a boy of thirteen has scored, say, ninety marks in a particular test. To know whether he is clever, average or dull, his marks must be Compared with the average achieved by boys of thirteen in that test.
In 1906 the psychologist, Alfred Binet(1857—1911), devised the standard in relation to which intelligence has since been assessed. Binet was asked to find a method of selecting all children in the schools of Paris who should be taken out of ordinary classes and put in special classes for defectives. The problem brought home to him the need for a atandard of intelligence, and he hit upon the very simple concept of "mental age".
First of all, he invented a variety of tests and put large numbers of children of different ages through them. He then found at what age each test was passed by the average child. For instance, he found that the average child of seven could count backwards from 20 to 1 and the average child of three could repeat the sentence: "We are going to have a good time in the country." Binet arranged the various tests in order of difficulty, and used them as a scale against which he could measure every individual. If, for example, a boy aged twelve could only do tests that were passed by the average boy of nine, Binet held that he was three years below ave rage, and that he had a mental age of nine.
The concept of mental age provided Binet, and through him, other psychologists, with the required standard. It enabled him to state scores in intelligence tests in terms of a norm. At first, it was usual to express the result of a test by the difference between the "mental" and the "chronological" age. Then the boy in the example given would be "three years retarded". Soon, however, the "mental ratio" was introduced; that is to say, the ratio of the mental age to the chronological age. Thus a boy of twelve with a mental age of nine has a mental ratio of 0.75.
The mental age was replaced by the "intelligence quotient" or "I. Q. '. The "I. Q." is the mental ratio multiplied by 100. For example, a boy of twelve with a mental age of nine has an "I. Q." of 75. Clearly, since the mental age of the average child is equal to the chronological age, the average 'I. Q.' is 100.
In order to judge a child' s intelligence, his marks in a test must be compared with marks gained by
查看答案
搜索结果不匹配？点我反馈
更多问题
What's the author's attitude towards the future of earthquake control ？
The main task of Auburn University's Institute for Biological Detection Systems is to find
Performing physical examinations is whitin the capacity of the artificial nose being developed.
Awareness of earthquake hazards is now well developed in many countries, and the U. S. Geological Survey has recently published a map showing the relative probability of earthquake activity for various areas in the United States.
The major hazard represented by seismic events along the great earthquake belts of the world has now been clearly recognized, and a great deal of research money and effort is being directed toward earthquake prediction and possible control. Active fault systems, such as the San Andreas fault in California, are carefully monitored for observable changes that could indicate an impending earthquake. Although the nature of earthquakes and earthquake belts are rela tively well understood, the possibility of accurately predicting major earthquakes, much less controlling them, still appears remote.
Probably the most intriguing development in this field relates to the Rocky Mountain Arsenal earthquakes near Denver, Colorado. In 1962 injection of fluid wastes into the Precambrian basement rocks nearly 4000m below the ground surface was followed by a series of small earthquakes. Studies of this phenomenon have indicated that the injected fluid lubricated a fault zone under stress and thereby promoted release of seismic energy. Experimentation at the site is still going on, but the connection between the fluid injection and earthquake activity was quickly rea lized. Accordingly, the suggestion has been made that potentially destructive earthquakes could be converted into numerous nondestructive minor earthquakes by using fluid injection techniques. Thus, although man has no hope whatever of controlling the major earth movements that lead to earthquakes, he may in some cases be able to influence the manner in which earthquake energy is dissipated.
Which of the following can be the best title for the passage？
微信支付 
支付宝支付