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    Intelligence Quotient (IQ) and Wechsler Intelligence Scale


    To find a person’s IQ, it was thought that if you divided a person’s mental age by their chronological age and multiplied the sum by 100 you would get their IQ.

    IQ = mental age ÷ chronological age • 100

    For example, if you are 16 years old, and your mental age is that of a 19 year old, you would take 19/16 X 100. The answer would be your IQ. So, 118.75, according to the intelligence quotient, is your IQ.

    The formula for the intelligence quotient did not stand ground for too long, as Binet’s test focused only on verbal assessment.

    David Wechsler identified a problem with Binet’s test and developed a way in which to improve his test. Wechsler devised a way to test the verbal scale (as Binet did) and nonverbal scale called the performance scale. This performance scale would allow the student to focus on problem solving without words. The child would be given a manipulative such as a puzzle and told to create the same design. Wechsler not only devised a test for children, called the WISC (Wechsler Intelligence Scale for Children), he also devised a test for adults called the WAIS (Wechsler Adult Intelligence Scale). It was Wechsler’s goal to have the two components—verbal and performance scores—to have a combined total for a person’s IQ.

    Now that you know a few tests to measure intelligence, let’s explore some more about what it means to be intelligent.

    Mental Age The level of intellectual functioning in years.

    Chronological Age The amount of years (according to birth) a person has entered.

    David Wechsler An American psychologist well-known for his development of the Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Intelligence Scale for Children (WISC).