Progress Update #2

Hi all!


I’m a bit late catching up on blog posts, because at this point I’ve completed my project, but in the second week of my research I looked in more depth at the Minnesota Multiphasic Personality Inventory (MMPI) and the Myers Briggs Type Indicator (MBTI) to try and determine whether or not either of them is considered reliable and/or valid. What I found, as expected, is that the results are mixed. For the MMPI, because it is most frequently used in clinical settings as a diagnostic tool, the studies I found related mostly to its reliability in identifying subjects with abnormal personalities. I generally found support for the MMPI as a diagnostic aide, valuable because it assesses patients on 10 different clinical scales and thus provides a multifaceted picture of any one individual’s psychopathology. However, the MMPI-2 (the most updated form of the MMPI) contains 567 true/false questions, so there is some concern about internal reliability. In other words, do people answer the questions as carefully and accurately in the second half of the test as they do in the first half? To combat this, the MMPI has validity scales which are designed to make it apparent when a subject’s responses are affected by test-taking fatigue.


The MBTI, on the other hand, is not as trusted in psychological spheres in regards to reliability and validity. Most psychologists agree that the MBTI is not valid as a measure of personality because it measures personality traits on a binary. It relies on Carl Jung’s theories of trait development as justification for doing so, but most modern personality tests that are used by psychologists measure personality traits as continuous variables– that is, on a spectrum rather than as a binary. Another criticism of the MBTI is that it predicts personality traits as definite characteristics which separate people into disparate groups based off of their four-letter designations, but the data which has been collected on the MBTI shows far to much similarity across different personality groups, and far too much variation within them, for this to be accurate.


In the third week of my research I collected information on the Eysenck Personality Questionnaire and the NEO Personality Inventory. I will be discussing those in my next blog post, so if you’re interested, stay tuned!


Virginia Wyatt