A behavior genetic analysis of vocational interests using a modified version of the Jackson Vocational Interest Survey

The purpose of the present study was to examine the scale properties of a modified version of the Jackson Vocational Interest Survey (JVIS; Jackson, 1977) and to examine the heritability estimates of the 34 vocational interest scales and resulting factor scores. Two modifications to the questionnaire were conducted. The number of items was reduced to 170 (from 289 pairs) and the ipsative response format was changed to a 5-point Likert scale. Results based on 742 individuals suggest that the revised scales have good scale properties with an average Cronbach’s α of .76 even though each scale consists of only five items. Thirty of the 34 vocational interests were found to have a genetic component with heritability values ranging from 37% to 61%. Four of the interest scales were found to have common environment effects between 28% and 46%. An exploratory factor analysis found that the modified interest scales could be reduced to seven factors. Univariate genetic analyses of the factor scale scores demonstrated that six of the seven had a genetic component and one was found to be best explained by common and unique environmental effects.