A lot of Israeli companies use handwriting tests in their hiring decisions. Don't ask me why, it's a meme that has hung on there for some reason. Does that mean graphology has predictive power? After all, companies are using it!

Of course not. All the companies are simply wrong. They're falling for management/hiring fads, or relying on old superstitions. This happens all the time. "Companies are using it" says nothing about whether it's actually reliable.

Specifically, many studies and meta-studies have failed to show correlation between MBTI results and job performance. Here is one such summary: http://www.opd.net/abstracts5.html

That's meaningless unless you confirm that their fitness for that task was actually correlated to their MTBI, e.g. by mixing those "fit" and "unfit" (based on MTBI) on the same task and comparing their performance. I'm pretty sure most companies don't do this. They just assume MTBI has predictive power and use it anyway since it gives them something to go on besides gut instinct.

Well, I know for sure that a person with an INTJ personality type is not suited for marketing and sales (statistically speaking of course). Would you claim otherwise?

Yes I would. Given the inconsistency of results that the Myers-Briggs test outputs for individuals, the personality of that person who tested as an INTJ could be far from it normally.

Furthermore, your willingness to buy into the narrative (and others' willingness to also believe it) that by categorizing certain people into stereotypes and assuming that most of these people tend to excel at a particular set of tasks is most likely what limits them from excelling at tasks that lie outside of their respective sets just as much as their true predisposition to not excelling at them.

Then please point me to the research, because the article does a lousy job at it.

Saying that any profiling technique has zero predictive value is a very bold claim.

Even one's astrological sign has predictive value: [1]. And yes, this has been scientifically proven.

[1] http://www.medicaldaily.com/how-birth-month-influences-perso...

Why is it the job of the skeptic to prove that a profiling technique does not have predictive power? Shouldn't you have to prove that it does?

Because it is very hard for a test not to have predictive power.

For example, companies fruitfully extract predictive power from whether a user clicked a link or not. Facebook extracts predictive power from whether users like videos, et cetera. So why shouldn't an elaborate test that was developed to have meaning, not have any predictive power?

Not having predictive power means it is not better than chance at predicting any X.

There are results that show MBTI has no predictive power against job performance. It has not been tested against any other measure.

That said, MBTI shows bad orthogonality in the factors in its response. This suggests the factors are ill defined.

> There are results that show MBTI has no predictive power against job performance.

Could you provide a reference?

Provided by another person in this thread already.

Don't invert the burden of proof.

How do you know that?

Have you done any controlled experiment to test this hypothesis?

The fact that (some) companies may use it to test if a person is fit for certain tasks doesn't mean that it really indicates whether a person is fit for certain tasks.

Let me devise a test. The test is just "are you a man or a woman?".

Does this have predictive power? Yes. If I needed somebody to take care of small children, would this test be useful? Yes of course. If I had to pick people blindly for this task, except for the results of this test, then this test would be very useful. Now, MBTI is more sophisticated than this simple test. So to say that it has no predictive power is just silly.

While I'm not a huge fan of Myers-Briggs (or rather, how it's used), that's not what I'm saying.

I'm saying that the fact that some people are using it for some purpose doesn't mean that it's actually useful for that purpose.

As for your response, the burden of proof really lies with its proponents - is there any proof of its alleged predictive power?

Strictly speaking you are right, my logic was flawed (hidden assumption). But let's stick with the orignal issue here, which is whether the test is predictive.

Agreed - this is why I asked whether there is any proof of its alleged predictive power.

Without this, I don't think it's reasonable to assume that it is in fact predictive.

Yes, but the point I'm trying to make is that the claim that any test has zero predicitive power is actually pretty bold.

For example, the simple test of whether a user clicks a certain link or not already has predicitive power (companies are using this, fruitfully). So a more sophisticated test like MBTI certainly has some predictive power.

This is a completely bogus argument. Phrenology[1] on its face sounds pretty sophisticated, but it still has zero predictive power.

[1] https://en.wikipedia.org/wiki/Phrenology

Read this: http://www.medicaldaily.com/how-birth-month-influences-perso...

Unless it is demonstrated to have some predictive power, it isn't certain at all.

Additionally, the added (relative) complexity doesn't imply anything about its qualities.

According to your logic, sophistication implies better predictive power. You completely ignore the fact that someone could devise a very elaborate system for judging e.g. fitness for a certain job, make very good assumptions and work very hard and still achieve poor predictive power.

True, but not very likely.

> MBTI has predictive power; for starters, it is used by companies to test if a person is fit for certain tasks.

This is a null argument.

Unless you show that those predictions actually assess whether someone is fit for those tasks this is absolutely content free.

That kind of makes sense, in a kafkan way, in a society so full of preparatory courses that will teach you how to do a test (instead of the contents of the test), or how to perform in interviews.

You're saying that, because companies use it to test employees, that means it has predictive power? Or is it that companies BELIEVE it has predictive power, so companies use it?

I suppose that demonstrates that MBTI had predictive power as to whether one will be hired by one of those companies, but it doesn't demonstrate anything beyond that.