An intelligence test for which the scores are normally distributed has a mean of 100 and a standard deviation of 15. In order to figure out the score from a Wechsler test a normal curve must be made. A normal curve is the symmetrical curve that represents the distribution of scores on many psychological attributes; allows researchers to make judgments of how unusual an observation or result is. Ninety-six percent of all people within 30 points of 100 on the Wechsler intelligence score sheet, which falls into the average category. About 2 percent of the population scores 69 and below which falls into the mental retardation range. Mental retardation is a condition in which demonstrate limitations in the ability to bring adaptive skills to bear on life tasks. About 2 percent of the population score above 130, this falls into the range of mental giftedness. Three criteria categorize gifted children in any domain include: precocity, independent learning, and a passion to master.
There are three ways to test if a test is bias or not and they include standardization, validity, and reliability. Standardization of a test is the normalization of a test, that is, the finding of certain normal scores when the test is given to a pilot group who are similar to the people taking the test. After finding the mean norms and the standard deviation, the process of standardization should make the test results fall into a rough bell curve. Without standardization, all of the people taking a test could end up with all wrong or all correct answers, making it impossible to distinguish between each. The Validity of the test, usually considered the most important of the three factors, is how much a test really differentiates between students as it is supposed to, how accurate it is in its findings. Reliability is the consistency of a test for measurement. It ensures that a person who takes a test three times in...