The extension of Holland's Occupational Classification to all occupations in the Dictionary of Occupational Titles

Abstract

Two methods are presented for extending Holland's occupational classification to include all occupations in the Dictionary of Occupational Titles (DOT). Holland's classification is based on a theory of personality types; occupations in the classification are organized into six major categories (Realistic, Investigative, Artistic, Social, Enterprising, and Conventional) and subcategories using the same concepts. The methods given in this article enable translation from any DOT occupational code (a six-digit number) into the corresponding Holland occupational code. The first method is essentially an application of Bayesian statistics using 399 occupations in Holland's Occupational Classification. The second method was developed by using the definitions of each DOT group (first three DOT digits) and assigning the Holland code which seems theoretically consistent with the DOT definition. The conversion methods are tested and compared on four occupational samples. An evaluation of the usefulness of the methods is given.