The Multifactorial Nature of Extraversion-Introversion in the Myers-Briggs Type Indicator and Eysenck Personality Inventory

The study was designed to test the construct validity of extraversion-introversion and to explore the nature of the concept as measured by the Myers-Briggs Type Indicator (MBTI) and the Eysenck Personality Inventory (EPI). The psychometric properties of the MBTI have been inadequately studied, whereas those of the EPI have been investigated extensively. Responses of 840 subjects to the two measures were submitted in toto to factor analysis. Of the seven factors retained, three measures of extraversion appeared: Factor 2 (a sociability component), Factor 4 (an impulsivity/non-planning component), and Factor 7 (a liveliness/risk-taking/jocularity component). Findings supported the view of extraversion-introversion as a complex construct (Eysenck and Eysenck, 1977; Guilford, 1977; Howarth, 1976). The Myers-Briggs Type Indicator-Extraversion Introversion (MBTI-EI) and the Myers-Briggs Type Indicator-Judging Perceiving (MBTI-JP), scales were found, surprisingly, to be factorially valid measures of impulsivity/non-planning. Implications and suggested research are discussed.