Participants and Design. The majority of the data was gathered from 1,061 individuals from employment service offices, junior colleges, trade schools, and other government agencies located in four regions across the United States: Michigan, New York, North Carolina, and Utah. These participants were administered the Interest Profiler and the Interest-Finder in a counter-balanced fashion. Two groups of individuals also participated in the test-retest portion of the study. Junior college/vocational students and college students were administered one of the instruments on two separate occasions, with approximately one month elapsing between the two administrations. The Interest Profiler was administered twice to 132 participants, and the Interest-Finder was administered twice to 120 participants.

Similarities to the Interest-Finder provided evidence of convergent validity for the Interest Profiler. A principal components analysis indicated that the two instruments had similar factor structures. Equivalent scales from both measures were highly correlated, also supporting the convergent validity of these measures.

According to the Holland model, however, the correlations for the Interest Profiler suggest a problematic Enterprising scale, because this scale correlates too highly with the Artistic scale and not highly enough with the Social scale. There was also a large difference in the mean Enterprising scores for the two measures. Although Interest-Finder items focus on high-level business and law activities, Interest Profiler items include many low-level sales jobs in an attempt to cover all prestige and education levels. Preliminary analyses indicate that these low training level items are not consistently perceived as Enterprising activities by assessment takers. The Interest Profiler introduces more variability into the Enterprising Interest Area and perhaps, in the process, loses conceptual unity. Nevertheless, it is important to keep in mind that these results are based on comparisons with the Interest-Finder. Comparisons to another RIASEC instrument may lead to different conclusions.

Also, according to the Holland Model (Holland, 1985a), both of the instruments exhibited a gap between the Realistic and Conventional Interest Areas (i.e., correlation between the two scales was too small). The presence of this gap has also been found in data from other Holland-type measures. Whether the Realistic-Conventional gap reflects the nature of vocational interest structure or a choice of items within the scales is still unknown.