The Mysterious Dark Arts of the MBTI

Even at its most fundamental expectation of measurement, namely counting, the MBTI is deficient. We simply cannot use it to measure anything because it is firstly, not uni-dimensional and secondly, not reliable. Not because we hate Katharine and Isabel, but because they unwittingly used a flawed theory. Good psychological models like the Big Five-based assessments and the Occupational Personality Questionnaire of SHL can generally be revisited using proper measurement development tools like Rasch analysis because they are fundamentally sound from a construct perspective. They have the fundamentals of proper psychological measures in place and are not constrained by a single psychologist’s perspective on personality.