Myers-Briggs Type Indicator (MBTI) is a personality test designed to assist a person in identifying some significant personal preferences. Katharine Cook Briggs and her daughter Isabel Briggs Myers developed the Indicator during World War II, and its criteria follow from Carl Jung‘s theories in his work Psychological Types.
The Indicator is frequently used in the areas of pedagogy, group dynamics, employee training, leadership training, marriage counseling, and personal development. However, scientific skeptics and academic psychologists have criticized the indicator in research literature, claiming that it “lacks convincing validity data” and could be an example of the Forer effect.
The MBTI includes 93 forced-choice questions, which means there are only two options. Participants may skip questions if they feel they are unable to choose. Using psychometric techniques, such as item response theory, the MBTI will then be scored and will attempt to identify which dichotomy the participant prefers. After taking the MBTI, participants are given a readout of their score, which will include a bar graph and number of how many points they received on a certain scale. Confusion over the meaning of these numbers often causes them to be related to trait theory, and people mistakenly believe, for example, that their intuition is “more developed” than their sensing, or vice versa.
During construction of the MBTI, thousands of items were used, and most were thrown out because they did not have high midpoint discrimination, meaning the results of that one item did not, on average, move an individual score away from the midpoint. Using only items with high midpoint discrimination allows the MBTI to have fewer items on it but still provide as much statistical information as other instruments with many more items with lower midpoint discrimination. The MBTI requires five points one way or another before it is nearly as sure it can statistically be concerning a preference.
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