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March  2008 | Issue 32

The "Aha!" Report

What's the "AHA!" REPORT all about?
This series of newsletters contains AHA! information to help people and organizations hire the best employees, make the best promotion decisions, retain the most qualified people, maintain the widest applicant pool, follow best practices, and (if you are subject to US law) remain aware of EEOC hot-spots.

A Rogue Psychologist Among the Cubicle-dwellers

In a recent edition of the comic strip Dilbert, the pointy-haired boss inflicted something called the Dogbert Personality Predictor Index on his team. The test was, of course, a no-win proposition for the hapless employees. A sample question, “How would other people describe you?” offered only three options “A) Angry loner; B) Embezzler; C) Lazy.”

True, the aim of the test was to help management “leave you in the dead-end job that most closely matches your lack of potential.” Unfortunately, the Dogbert instrument shares a disturbing similarity with many real-world personality assessments: the test, and presumably the scoring, have no obvious predictive relationship to job performance. Which characteristic is more closely correlated with success as an engineer: “unidentified hominid” or “inappropriate toucher?” How about “INTP” or “ESTJ”? Get it?

Personality Testing, Right or Wrong

It’s true that engineering, legal, IT, or actuarial jobs largely require technical skills. It’s relatively easy to test for these – and rigorous professional credentialing often helps do the job for us. However, it also takes certain personality factors to make a good job fit.

If being an “angry loner” isn’t a useful indicator of job performance (actually, it probably is, but I can think of no legally defensible way to measure it), how can we tell which personality factors are important? And how do we measure them?

The Wrong Way(s)
Any pre-screen test, whether an interview, test, resume review, or application form, is supposed to anticipate how the applicant will perform on the job. In a perfect world, good scores predict good performance, and bad scores predict bad performance (assuming that we hire applicants with bad scores).

Well, there's a right way and a wrong way to link scores to future job performance. Unfortunately, the wrong way is the norm. It comes in two varieties:

  • Someone likes XYZ test, gives it to every applicant, and plays amateur shrink.
  • Someone gives a one-size-fits-all test to current employees and correlates scores with job performance.

Both varieties are filled with mistakes. The first is common among most organizations I know. The second is common among folks who might have taken a class in statistics, but skipped the class in measuring human performance. Either way, they tend to turn away good employees and hire bad employees.

What is This Thing Called Performance?
If we want to use a pre-hire test, common sense says to first determine what factor we want to measure. Second, choose an accurate and trustworthy test that measures this factor. Third, make sure the test predicts job performance. Sound simple? Read on.

Some people think they can measure "performance" by looking at performance appraisals or supervisor ratings. However, we all know performance ratings are often primarily personal opinion shaped by office relationships and politics. As a result, most performance review ratings mean that an employee is either:

  • Unskilled at shifting blame for his or her mistakes and/or unpopular.
  • Highly skilled at shifting blame and/or charismatic.
  • Skilled at corporate camouflage and/or equipped with radar-evading technology.

“Harder” performance data is often not much better. In general, any data that can only be evaluated at the end of a long performance period is error-prone. Sales volume, for example, is fuzzy because it's a function of persistence, fact-finding, learning, strategizing, presentations, adapting to buyer personalities, economic conditions, market conditions, and so forth.

To use an analogy, if you want to measure the quality of grapes in a fruit salad, you cannot put all the fruits into a blender, press “liquefy,” and come back six months later with your grape-o-meter. Performance data must be easy to see and easy to measure.

Big Nets Often Contain Big Holes
Let’s move on to Wrong Way #2, the folks who give a multi-factor personality test to everyone and then examine the results to identify correlations. Even if they can do the math, this is a major mistake, primarily because a correlation is not always a causation. In other words, just because two things are statistically associated does not mean one causes the other.

Statistics is deaf, dumb, and blind. Only a human being can decide whether one factor causes the other. For example, organization or teamwork factors may correlate with performance, but if organization and teamwork don't cause performance, then hiring people based on these scores will reject qualified candidates and hire unqualified ones.

How Many Factors?
Pick a test, any test. The DISC personality model is a widely used tool; just check off a few dozen adjectives and you can get a mini-novel. It looks good, but how comprehensive or accurate is the DISC? It turns out to be based on a two-factor theory that is almost 80 years old, which states that personality is a function of being either active or passive in a friendly or unfriendly environment. Does this sound sufficiently comprehensive to define your job?

Take another example, with just one variable. I once visited a company where the HR guru only hired people who excelled at teamwork. After a few years, it had 300 employees who would not schedule a meeting unless everyone could attend, could make a decision unless everyone agreed, and dared not confront a production problem because it might hurt someone's feelings. Did they get the results they expected? No. They got the results they measured.

University research shows that it takes about nine to ten factors to predict job performance. Six or seven are based on job fit and three are based on job attitude. It is probably a good idea to check your test vendor to see if the test you are using was developed based on this research. If not, it probably won't either predict the performance or attitudes you need.

Statistics
Statistics, as I said above, has some serious handicaps. It can only measure associations under the right conditions. For example, data sets smaller than about 25 people are filled with too much individual information and not enough group information. So comparing the characteristics of 15 high producers with 15 low producers is probably going to involve a substantial amount of error. The bottom line? Trustworthy statistics needs large numbers of people to be accurate.

What about the size of correlation? Should we celebrate a correlation of .30? Does it mean we have a 30% relationship? No. It means we have a 9% relationship. The technical details can be used as a non-habit-forming remedy for insomnia, but in short, correlations have to be squared to learn how much performance they predict. People who do not understand statistics are easy to fool.

Wrap Up
Personality can be a very important thing to measure pre-hire because it can provide considerable insight into job performance. However, before you can trust a personality test to predict performance in your job, you have to clearly define what you want to predict; identify the personality factor that causes it; find a test developed specifically to measure that factor; either conduct your own study or transport someone else's work; and finally, realize that personality is only one part of the puzzle.

Otherwise, your organization would probably do just as well to have an evil cartoon dog handle your pre-hire assessment program.

 


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