Understanding the Stanford Binet Intelligence Scale

Most of us have heard about people with high IQs. People that are so brilliant they make mind bending discoveries. These great minds are so intelligent they often experience worldwide fame, adoration and awe. People such as Albert Einstein and Stephen Hawking are perhaps the most widely known persons of high IQ. Stephen Hawking's is reported to be 160 and Albert Einstein's was thought to be somewhere between 160 and 190. Actress Sharon Stone is reported to have an IQ of 154 and Terence Tao is reported to have an IQ between 225 and 230. At 24 he became the youngest doctorate (received at age 20) professor to ever be hired by UCLA.

While we understand that these people are brilliant and are able to understand complex subjects such as math and science in ways that send the average person into a coma, most of us don't understand how the IQ is determined and what that number really means. In order to make IQ an easier concept to understand and measure, the Standford Binet Intelligence Scale was created. In order to understand the scale, one must first understand the test. 

The Stanford Binet Test

The test is comprised of four sections: Short-Term Memory, Quantitative Reasoning, Verbal Reasoning, and Abstract/Visual Reasoning. Each section can take up to half an hour to complete and the final intelligence is scored from the composite of these scores. This test was standardized using large groups of each age category and background that was representative of the United States in order to achieve a scale. This means that it was administered to several groups and their scores were calculated and an average found for each group. This allowed testers to determine a below average and above average intelligence quotient.

The Score

The four tests are scored. Each test score is the number of correct answers. These numbers are added together and are considered the to be the test taker's intelligence score, also known as general reasoning ability and are called SAS -- Standard Age Score which is correlated to the test takers age. Since the Stanford Binet has tests for each age grouping, it is believed to offer a more accurate accounting of intelligence. 

These scores(the composite score and the section scores), all have a mean or average score of 100 with a deviation of 16 which is the same format as traditional IQ tests. This means that a test-taker with a score of 100 would be considered to be of average intelligence. Since 16 is the standard deviation, if one scores 84 they would be considered one standard deviation below average. Similarly if one scored 116 they would be considered to be one standard deviation above normal. 

Because the Standford Binet Intelligence Test has multiple components and subsets, only a trained, qualified person such as a psychologist is able to truly evaluate the results accurately. Even though the scoring of the Standford Binet Intelligence Test is similar to that of traditional IQ tests, they still require a professional analysis.