INTELLIGENCE TESTS

Intelligence tests are the oldest and most frequently used psychological tests. The tests scores are expressed in the form of intelligence quotients.  

Psychologists are not one opinion about the concept and definition of intelligence. The various definitions of intelligence can be divided into three groups.

1. Definitions which define intelligence in terms of adjustment or adaptation of the individual to his total environment and/or its general mental adaptability to new issues and new situations in life. It may be called an individual's capacity to adjust successfully to novel and changing situations in his life. Thus, an intelligent individual is one, who can change his behaviour more easily to cope successfully with his ever-changing environment. 

2. The other group of definitions explain intelligence in terms of learning or person's educability and an intelligent person is capable of learning more extensively and easily from his own experience.

3. The third group of definitions consider intelligence in terms of an individual’s ability to carry on abstract thinking which in most parts, depends upon an individual's capacity to make use of abstract processes like concepts' verbal or numerical symbols for solving the numerous problems the individual encounters in his life. According to this view, a person more capable of forming and utilizing such symbolic processes in the solutions of his problems is regarded as comparatively more intelligent.

An examination of these classes of definition reveals that the processes of adjustment, learning and abstraction are interdependent. 

An organism absolutely incapable of learning will have no capacity to react differently to different situations and will be naturally incapable on any effective adjustment to his environment.

 Learning, at least in human beings, is impossible without the use of some symbolic processes. This is perhaps the  reason why many psychologists believe that a man's capacity to make use of symbols  and his ability to carry on abstract thinking are the very basic processes all human intelligence involve in. Without them he is unable to think through a problem, and spends his time and effort on sheer trial and error in action, which is so characteristic of animal behaviour. 

French psychologists Alfred Binet and Simon in the 1905 made the earliest effort to measure intelligence systematically when the world's first psychological test to measure intelligence was devised. The test was refined in many of its later revisions, first in France and then in America. The American version of the test is known as the Stanford- Binet test of intelligence and its latest revision appeared in 1960. These tests constituted a great landmark in the history of testing; and all the psychological testing that has developed in the last seventy five years is either application, elaborations or refinements of the original ideas of Binet and the other early test constructors. Since Binet, a number of intelligence tests have been constructed - most of these tests measure such functions as learning, memory flexibility in thinking, insight, alertness, speed of thinking and creative or inventive reasoning.  

Intelligence tests may be broadly grouped into two categories.

1.    Those tests which provide an overall score of intelligence like Intelligence Quotient (IQ) or mental age (MA).

2.    Those that provide some indication of a person's standing in various constituents of intelligence.

The first type of tests is known as tests of general intelligence whereas the second type is called tests of mental abilities.

Binet first developed the concept of mental age (MA) which is very simple in its conception. We are aware that an average child of a given intelligence is able to perform certain functions such as obeying simple commands, building certain structures from blocks, interpreting pictures or giving meanings to words.  If the Tested child exhibits an overall ability to perform such crucial operations of say, a ten year old child, he is said to have a mental age of ten years (MA=10). If the child is also ten years old, we can say that his mental age is equal to his chronological age.  But a ten- year child may also perform the average functions which a child of 11 , 12, or 13 years could also perform; such a child then has higher mental age than which may follow from his chronological  age. If a ten year old child is not able to pass the task set for his age and is able to pass tasks which are meant for a five year old child, his mental age is then five years.

That means he is retarded in his mental ability. Once we are able to determine the mental age of a child on the basis of his performance on the tasks which can be averagely performed at each age level, it is only a short-step to determine his IQ. IQ is conceived as the ratio between mental age (MA) and chronological age (CA). In order to avoid fractions the ratio is multiplied by 100. Thus the formula for determine IQ reads as:

                   IQ = MA/CA x 100

If the IQ is hundred, the MA and CA are the same, or the IQ is average, that is, 100. If there are discrepancies in the MA and CA it can be either above hundred (better than average intelligence for his age level) or below hundred (lower than average intelligence for his age level). Thus by finding the IQ we can state whether a person is of average intelligence, or above or below it and also say how much above or below he is from the average meant for his age.

There are many insights that psychologists have developed on intelligence testing. The uses of intelligence testing are immense in industry because industrial jobs differ greatly in complexity and higher the job hierarchy the higher levels of intelligence are usually required on the part of the persons filling the jobs. The intelligence is one of the most stable characteristics of behaviour and though it grows with time the heights reached by an individual in the prime of his youth remain relatively stable throughout the life for most individuals. This makes IQ a more trustworthy measure of human intelligence.

There are several tests of general intelligence among like the Stanford Binet Test of intelligence and the Weschler Adult Intelligence Scales (WAIS) meant for adult age groups. These tests are used on single individuals and needs a person well versed in their testing procedures and interpreting the performance of the individual. Though the Stanford and Binet tests and the Weschler Scales give an overall IQ score, they are considerably different in their conception and can be also put to a wide variety of uses.  In modern selection practice, however, they are rarely used because of the time required to test a person fully.

Among the most widely used tests in industry, mention may be made of the name of the Otis Self Administering Tests of Mental Ability which are available in two forms, for school going children and college students and adults. In industry the adult forms of these tests have been applied for almost every type of job. The success of tests as a screening instrument of course, differs from situation to situation, but it has been found extremely useful with lower level jobs.

The Wonderlic-Personnel Test is an abridged adaptation of the Otis Test known as the Wonderlic Personnel Test. It is a quick test which requires only twelve minutes time to answer and yet can give results comparable to the original Otis Tests (time limit 30 minutes). The items of the Wonderlic Tests are so selected that they can distinguish between a poor worker and a good worker on different industrial jobs. The test manual provides special instructions for using its score. These tests have proved of great relevance particularly in the selection of clerical workers.

Present trend in testing is towards using more and more specific tests, which can tell how an individual scores on various constituents factors of intelligence. Most of these tests give scores on each separate factor and can be combined in a battery (a group of tests) to serve specific purposes in selection for various jobs, depending upon  which factors of intelligence enter the job. Some such tests are outlined below.

An example of multifactor test is the Chicago Test of primary Mental abilities L.L.Yhurstone developed who published a series of multifactor tests known as the Chicago Tests of primary abilities.  More condensed and shorter editions of these tests were later named as the SRA Primary Mental Abilities.  The factors have been isolated by using the factor analysis. A single booklet makes the tests available and it takes about two hours for complete administration.

In addition, a great variety of intelligence tests are available for industrial purposes such as: 

1.    Verbal Reasoning

2.    Numerical Ability

3.    Abstract Reasoning

4.    Space Relations

5.    Mechanical Reasoning

6.    Clerical, Speed and Accuracy, and

7.    Language Usage

This test is used very extensively in industrial selection.

Intelligence tests are the oldest and most frequently used psychological tests. The tests scores are expressed in the form of intelligence quotients. 
An IQ is the ratio of the mental age to the actual (chronological) age. When the mental and chronological ages correspond, the IQ is expressed as 100. It is assumed that intelligence is distributed normally throughout the population.  Intelligence tests are the tests of general intellectual abilities to measure not a single intelligence trait but rather a combination of abilities consisting of memory, vocabulary, verbal fluency, and numerical ability. For adults, of course, the notion of mental age divided by the chronological age would not make sense.