Personality tests for job applicants are a waste of time

Yes, you read the title right. I think that personality tests for job applicants are a waste of time.

Why? Because we don’t know anything about human nature.

You don’t believe me?

OK then, would you believe Judith Rich Harris (link to Wikipedia article)?

She’s written a great book, “No Two Alike”. In it she describes how identical twins who are reared in the same house and in the same way, have a correlation of about 0.5 on personality tests.

If you’ve ever studied statistics (cue memories of tedious classes during psychology degree) then you’ll know that 0.5 is actually quite high. But, here’s the thing, it’s not that high even for identical twins.

Judith also points out that,

“the identical twin of someone who has experienced a major depression has only a 40 percent chance of becoming seriously depressed…the identical twin of someone with schizophrenia has only a 48 percent chance of developing the disorder.”

Psychologists have spent years debating the relative influence of nature vs nurture on personality. Yet studies like these make me think that we don’t really know that much about personality after all.

My take on Judith’s book is that our ‘personalities’ are in a constant state of flux. We flex our ‘personality’ (whatever that is) as we move between different social spheres and from one relationship to another.

For example, are you the same person at work as you are at home? Do you exhibit the same personality traits when you’re sitting in a church as you do at a football match?

How do you differ when you are talking to your boss compared to when you are talking to your child? Or is there simply lots of ‘talking down to’ taking place in both situations…

You may think that you’re the same person in every situation and all of the time. But many psychologists argue that the sense of Self is an ‘illusion’ that we all suffer from.

How then, can we reliably test a job applicant’s personality? I don’t think we can.

What do you think?