Wednesday, March 11, 2009

Facts Behind the Myth of Good Iq Score

You might have heard that somebody has obtained very good IQ score. Some may even show you their certificates to prove that they have got more than 120 IQ score. Higher the score, higher the intelligence level is presumed. However, such claims and assumptions are baseless, false and misleading. The highest IQ test score in one IQ test may not be equivalent to an average score of another test.

A good IQ score is a relative term. The initial score obtained by answering the items correctly is called a raw score. It is useless unless interpreted in meaningful terms by following the established norms. Even when two scores are processed through the psychometric principles, you can’t ignore the following important issues before determining a good IQ score:

Name of the IQ Test
Unfortunately, the psychologists have not succeeded yet to develop a perfect system of comparing two IQ scores got from different IQ test. Naïve comparison of two digits, however higher they may be, can’t help you to determine a good IQ score. First of all you need to know on what IQ test on which the highest score was obtained.

Difficulty Level of the Items
The second problem to determine a good IQ scoring is the difficulty level of the test on which the claimed good IQ score was obtained. Your score will decline with the increasing difficulty level of the items being offered. It is possible that you get two different IQ score with two tests having same label. One reason for this variance would be the difficulty level of the items. The test developers vary the difficulty level of the test with the change of age, education and some other important factors.

Content Variance
You can find a number of tests with the same name but with different content. Even when you obtain 120 IQ score on an IQ test of verbal capabilities, you mayn’t claim the same level on another test of the same label containing mathematical items. General IQ tests try to develop items from all categories of intelligence but modern day testing industry is getting more specialized with every passing day. You need to consider content variation while determining any score a good IQ score.

Time and Age Differences
You may have got 120 IQ score in your fifth grade, 115 in sixth and 110 in seventh grade. Apparently, your intelligence level is decreasing with each passing year. However, the actual position may be entirely different for a number of reasons including the label of the test, the difficulty level or even difference in the content. You can’t be sure that your highest IQ score is your good IQ score.

Difference of Standard Deviation Units
Originally, the mental age (MA) was considered sufficient to measure your intelligence. It soon proved useless and the term of intelligence quotient (IQ) was introduced. It was nothing more than a simple ratio of the mental age to the chronological age, multiplied by 100 to eliminate decimals. A score of 100 was considered an average IQ score and any deviation could place you in the range of above or the below average population. The system worked well unless it was proved that standard deviation doesn’t remain constant throughout your life.

Now different IQ tests use different levels of standard deviation. It is possible that one test use a standard deviation of 15 and another of 20. In such situation two apparent equal IQ score can’t be interpreted into equal level of the intelligence. Thus determining a good IQ score becomes further difficult.

Composition of the Samples
You may find guidelines about difficulty of test items, content, longitude differences and standard deviations in the manuals of the given IQ tests. However, you will rarely find the systems which helped the test developers to establish norms.

To establish norms, the test developers try to take a perfect sample of the subject population. However, there is so much variance in the general public that a perfect representative sample is almost impossible. The situation worsens when you try to compare IQ scores in different societies. Under the circumstances, no IQ score can be claimed as the best IQ score even when all other variables remain constant.

But What is Good IQ Score...?
It is sufficient to prove that any digit is insufficient to be claimed as a good IQ score. All such claims are misleading, inappropriate and unhelpful. Similarly, no score can be claimed as bad IQ score. Unfortunately, the testing industry cares very little to remove this misunderstanding either by intent or inadvertently.

-------------------
About the Author:

Psychometrics? Some believe in them and others reject them altogether. However, reality lies in between. Saqib Ali Ateel unlocks secrets of personality, intelligence, aptitude and testing at http://www.personality-and-aptitude-career-tests.com/art

Article Source: http://www.articlesbase.com/advice-articles/facts-behind-the-myth-of-good-iq-score-98607.html

No comments:

Google