Thursday, February 22, 2007
Personality testing basics: Part 1
If responses to my survey are any indication (see sidebar on main page), personality testing continues to be a hot topic out there.
There's a lot written about personality testing and a lot of advice given out. It can be difficult to know who to believe and which tests are appropriate for use in personnel selection.
This is Part 1 in a two-part post I will be doing on personality testing. This part covers some of the major research that has been done on personnel selection using personality tests; Part 2 will be an overview of some individual test products.
Every recruiter and assessment professional should be at least familiar with the major research findings in this area. Here are some of the major modern developments and articles to be aware of:
1. Although historically some personality researchers (e.g., Cattell) felt 16 or more factors were necessary to describe the major elements of personality, researchers in the 1960s found through their analysis that five seemed to do a satisfactory job: Openness to experience, Conscientiousness, Extraversion, Agreeableness, and Neuroticism (memory hint: OCEAN). Confirmation of this so-called "5-factor model" included research by Tupes & Christal (1961; not published until the early 1990s) and Norman (1963).
2. In 1965, Guion & Gottier publish an influential paper stating "taken as a whole, there is no generalizable evidence that personality measures can be recommended as good or practical tools for employee selection." This, combined with the rise of behaviorism, leads to a reduction in personality research until...
3. In the 1980s researchers once again began focusing heavily on individual differences and concepts like temperament and personality. This resulted in the re-emergence of the "Big 5" in, for example, Goldberg (1981; in here), Costa & McCrae (1987), and Digman (1989).
4. In the 1990s several important studies were published, including Barrick & Mount's highly influential 1991 meta-analysis which helped to reinvigorate research into personality testing in the workplace and showed that test results could have significant predictive ability (particularly Conscientiousness). Later that same year, Tett and colleagues publish another influential study verifying the usefulness of personality tests.
5. In 1993 Ones, Viswesvaran, and Schmidt publish research showing the substantial usefulness of integrity measures in predicting work behavior.
6. The 1996 introduction of the International Personality Item Pool (IPIP) by Lewis Goldberg allows personality researchers access to a publicly available personality research instrument.
7. In 1997, Jesus Salgado broadens the scope beyond the U.S. and Canada and publishes research indicating that personality measures, particularly Conscientiousness and Emotional Stability, predict job performance in the European Community.
8. In 1998, Schmidt & Hunter publish one of the most influential personnel research articles in history, meta-analyzing the major assessment methods. The authors state that the correlation values for conscientiousness are "large enough to be practically useful."
9. Hogan & Holland's 2003 meta-analysis shows that when you match what you're looking for (predictor) with what you measure (criteria), predictive ability can be even higher than previously reported, with correlations ranging from .34 to .43.
This is just a sample. Research into personality testing continues to be very popular, with many of the SIOP and IPMAAC conference presentations devoted to the subject. That's part of what makes it one of the most interesting, and controversial, forms of testing.