Assessing Holland Types on the Internet: A Comparative Study
This study examined the degree of similarity between scores on the Self-Directed Search and an online instrument measuring Holland types. A relatively high congruency score was found between the two measures. Implications for career counselors are discussed. ********** The theory of careers proposed by Holland (1985, 1997) characterized persons and environments as a single set of six types. According to Holland (1985), most people in our culture can be classified as one of the six dominant types (Realistic [R], Investigative [I], Artistic [A], Social [S], Enterprising [E], Conventional [C]). Thus an individual's personality (i.e., interests, values, abilities, fantasies) can be assessed by considering his or her three most dominant types. Workers are motivated to seek out work environments that complement their dominant personality types, thereby maximizing the chances of individual satisfaction and well-being. Holland (1997) advocated the use of three-letter codes to identify occupations consistent with a worker's personality type. In Holland's typology, both personality and environment are expressed in three-letter codes. A three-letter code is formed by selecting, from Holland's six types, the three types that most closely characterize the person or his or her work-school environment. The three-letter code provides a brief summary of what a person is like by showing the degree of resemblance to three occupational groups. For example, the three-letter code of CER suggests that the person has a dominant Conventional personality but also possesses the Enterprising and Realistic characteristics to a somewhat lesser degree. Extensive descriptions of six types can by found in Holland (1997). A vast number of career instruments are currently available to assess a client's three-letter code, most notably the Self-Directed Search (SDS; Holland, 1994). The Internet, however, has added immeasurably to this list of available instruments. And while the advancements to testing because of the Internet could improve assessment effectiveness, various unintended negative consequences may also occur, such as increased availability of tests with questionable validity and reliability (Sampson, 2000). For example, Oliver and Zack (1999) examined 24 no-cost career assessment Web sites and encountered numerous limitations among the sites. They recommended several research strategies to deal with these shortcomings including providing relevant psychometric data. Authors use many different techniques to demonstrate the validity of their tests. A test to measure cognitive abilities, for example, should demonstrate high correlations with tests that measure similar abilities. This is an example of convergent validating, a component of construct validity. Specifically, convergent validity is a process in which one instrument is compared with another instrument measuring the same construct (Drummond, 2003). Thus, this study attempts to measure the convergent validity of an online instrument, the Holland Personality Mosaic (HPM), by comparing its results with the results from the Self-Directed Search (SDS) using the Iachan Index (Iachan, 1984). METHODS The participants in this study were 30 masters-level graduate students (25 females, 5 males) in the Department of Psychology and Behavioral Sciences. The graduate students ranged in age from 47 to 21, with a mean of 26.6, most were Caucasian (21), followed by African-American (9). All the participants were volunteers and all were given 3 bonus points for their involvement. The participants were administered both the Self-Directed Search (SDS) and a printout of the Holland Personality Mosaic in class and instructed to complete each instrument outside of class and return the instruments the following week. To control for order effects, students were told to complete first the SDS. The Iachan Index was explained to all students and each student calculated his or her own index score. …