by 100 in order to eliminate decimals. The mathematical representation of this would be:IQ= (mental age / Chronological age ) * 100If a person being tested had a mental age equal to the chronological age it is said to have an I.Q. of 100, otherwise considerate to be performing at a normal level.This test, once efficient, had a technical difficulty due to the fact that the results of the test could not be compared at other age levels. Besides being incomparable with other age levels, the Mental Age IQ, otherwise known as the Ratio IQ, “proved very difficult to construct tests that meet psychometric requirements for comparability of ratio IQ through their age range. Therefore, due to this inefficiency, the Ratio IQ test has been replaced with the Deviation Test. The Deviation IQ is a standard score with a mean of 100 on a Standard Deviation that is similar to that of the Standard Deviation in the Standford-Binet IQ distribution. Although the Standard Deviation of the Stanford-Binet Ratio IQ is not exactly constant al all ages, it fluctuates around the median value slightly greater than 16. But if a Standard Deviation close to 16 were to be chosen when reporting standard scores in a newly developed test, the results of such tests can be interpreted the same way as the Standford-Binet Ratio IQ.It is important to keep in mind that the methods employed in finding traditional Ratio IQ’s are not that of the Standard Deviation IQ. These are not ratios of the mental ages and chronological ages. Another thing that we also have to keep in mind is that there are certain limitations when it comes to the Ratio IQ. Tests have shown that when a child reaches adolescence, to be mores specific, the age of 15, when he/she performs the test, there is no noticeable iq increasement.On the other hand, the deviation I.Q. can record the progress of an individual up to the time where he/she took the test. Also, this test is capable of i...
