The Strong Ring: A Basic Interest Model of Occupational Structure.

A classification system and spatial map of occupations were developed using the Basic Interest Scale profiles of 198 occupational incumbent samples (31,010 women; 32,421 men) from the Strong Interest Inventory. Profile shape was found to be similar for incumbents of both genders, allowing for an analysis of combined-gender samples. Using hierarchical cluster analysis, the authors identified 9 general interest areas subdivided into 19 occupational clusters. Nonmetric multidimensional scaling was used to create a spatial representation, producing a 3-dimensional ringlike structure called the Strong Ring. Dimension labels were identified using property vector fitting of O*NET variables. These dimensions were (a) Persuasion Versus Problem Solving, (b) Structured Versus Dynamic, and (c) Social Service Versus Solitary Work. This new model provides an organizational and interpretive framework for professional, technical, managerial, and skilled occupations. Of all widely used psychological tests, the Strong Interest Inventory, first published in 1927, has the longest history (Campbell, 1971). Research on the Strong Interest Inventory (herein called the Strong) has had a major impact on interest assessment and career counseling (Borgen, 1986). Of the many contributions, the introduction of the Occupational Scales (E. K. Strong, 1927), the development of Basic Interest Scales (BISs; Campbell, Borgen, Eastes, Johansson, & Peterson, 1968), and the use of Holland’s (1959, 1997) theory to organize and interpret interest scales from the Strong (Campbell, 1974) have had a lasting effect on interest measurement (Hansen, 1984). The 1994 edition (Harmon, Hansen, Borgen, & Hammer, 1994) of the Strong is organized around Holland’s theory, with BISs and Occupational Scales organized by Holland type. The purpose of the present study was to revisit the use of Holland’s RIASEC classification system with the Strong scales and to develop an alternative classification system and spatial model using the BIS profiles of the Occupational Scales incumbent samples. We propose using basic interest profiles to develop a new occupational classification system because these measures allow for a more detailed and representative model of vocational interests than the Holland system. Basic Interests