The Myers-Briggs Type Indicator

By: Bella Dalba

Boasting an average of two and a half million American participants per year, one of the most popular personality tests is the Myers-Briggs Type Indicator (MBTI), a psychometric assessment designed to measure psychological preferences in decisions and perception of the world. Originally based on the work of psychologist Carl Jung, the actual test’s methodology was extrapolated and developed by Isabel Briggs-Myers and her mother, Katharine, in 1962. 

Jung's typological model regards psychological type as similar to left or right handedness: individuals are either born with, or develop, certain preferred ways of perceiving and deciding. The MBTI sorts some of these psychological differences into four opposite pairs, or dichotomies, resulting in sixteen possible types. However, Briggs and Myers theorized that individuals naturally prefer one overall combination of type differences, in the same way that writing with the left hand is hard work for a right-hander. People tend to find using their opposite psychological preferences more difficult, even if they can become more proficient (and therefore behaviorally flexible) with practice and development.

The sixteen types are typically referred to by an abbreviation of four letters. The first letter (E or I) stands for the terms extraversion or introversion: extraversion implying "outward-turning" and introversion "inward-turning,” the specific definitions of which vary somewhat from the popular usage of the words. Both of the cognitive functions can operate in the external world of behavior, action, people, and things ("extraverted attitude") or the internal world of ideas and reflection ("introverted attitude").

People who prefer extraversion draw energy from action: they tend to act, then reflect, then act further. If they are inactive, their motivation tends to decline. To rebuild their energy, extraverts need breaks from time spent in reflection. Conversely, those who prefer introversion "expend" energy through action: they prefer to reflect, then act, then reflect again. To rebuild their energy, introverts need quiet time alone, away from activity.

Secondly, Jung identified two pairs of psychological functions: the two perceiving functions, sensing and intuition; and the two judging functions, thinking and feeling. According to Jung's typology model, each person uses one of these four functions more dominantly and proficiently than the other three; however, all four functions are used at different times, depending on the circumstances.

Sensing and intuition are the information-gathering (perceiving) functions. They describe how new information is understood and interpreted. Individuals who prefer sensing are more likely to trust information that is in the present, tangible, and concrete: that is, information that can be understood by the five senses. They tend to distrust hunches, which seem to come "out of nowhere.” They prefer to look for details and facts. For them, the meaning is in the data. On the other hand, those who prefer intuition tend to trust information that is less dependent upon the senses, that can be associated with other information (either remembered or discovered by seeking a wider context or pattern). They may be more interested in future possibilities. For them, the meaning is in the underlying theory and principles which are manifested in the data.

Thinking and feeling are the decision-making (judging) functions. The thinking and feeling functions are both used to make rational decisions, based on the data received from their information-gathering functions (sensing or intuition). Those who prefer thinking tend to decide things from a more detached standpoint, measuring the decision by what seems reasonable, logical, causal, consistent, and matching a given set of rules. Those who prefer feeling tend to come to decisions by associating or empathizing with the situation, looking at it 'from the inside' and weighing the situation to achieve, on balance, the greatest harmony, consensus and fit, considering the needs of the people involved. Thinkers usually have trouble interacting with people who are inconsistent or illogical, and tend to give very direct feedback to others. They are concerned with the truth and view it as a priority.

Myers and Briggs added another dimension to Jung's typological model by identifying that people also have a preference for using either the judging function (thinking or feeling) or their perceiving function (sensing or intuition) when relating to the outside world (extraversion). They held that types with a preference for judging show the world their preferred judging function (thinking or feeling). As such, TJ types tend to appear as logical and FJ types as empathetic. This developed into four separate categories: Analysts (NT), Diplomats (NF), Sentinels (ST), and Explorers (SF).

“Breaking down someone’s personality into something completely individual, while still being able to relate it to other people through categories, is kind of incredible,” says Sarah Dempsey, a Seckman High School senior.

However, some researchers have interpreted the reliability of the test as being low, particularly with regards to the test-retest reliability of the test. Studies have found that between 39% and 76% of those tested fall into different types upon retesting some weeks or years later, and large numbers of individuals have found that they get different classifications when retaking the test after just five weeks. There is also strong evidence that the different scales are correlated, and not independent as claimed.

One study reports that the MBTI dichotomies exhibit good split-half reliability; however, the dichotomy scores are distributed in a bell curve, and the overall type allocations are less reliable. Also, test-retest reliability is sensitive to the time between tests. Within each dichotomy scale, about 83% of categorizations remain the same when individuals are retested within nine months, and around 75% when individuals are retested after nine months. About 50% of people tested within nine months remain the same overall type, and 36% remain the same type after more than nine months.

“I’ve been an INTJ my entire life. I think it’s more difficult for introverts to change their thought patterns, but, because extraverts tend to draw their moods from others, their personalities seem to be more flexible,” said SHS senior, Claire Kinkead. 

In another study, when people were asked to compare their preferred type to that assigned by the MBTI assessment, only half of people picked the same profile. Critics also argue that the MBTI lacks falsifiability, which can cause bias in the interpretation of results.

A number of researchers argue that criticisms regarding the MBTI mostly come down to questions regarding the validity of its origins, not questions regarding the validity of the MBTI’s usefulness. Others argue that the MBTI can be a reliable measurement of personality; Robert Capraro, a psychoanalyst, believes that "like all measures, the MBTI yields scores that are dependent on sample characteristics and testing conditions.”

Either way, personality is subjective, and therefore difficult to measure objectively. The MBTI attempts to cross this barrier, and is arguably successful: the distribution of personality types reflects the diversity of the population. Though it remains a pop culture staple, the science behind it is increasingly validated.