The Dunning–Kruger Effect

Jeff Atwood over at Coding Horror wrote an article that got me thinking.  Apparently there are hordes of people applying for programming jobs who can’t even pretend to write a program.

I wrote that article in 2007, and I am stunned, but not entirely surprised, to hear that three years later “the vast majority” of so-called programmers who apply for a programming job interview are unable to write the smallest of programs. To be clear, hard is a relative term — we’re not talking about complicated, Google-style graduate computer science interview problems. This is extremely simple stuff we’re asking candidates to do. And they can’t. It’s the equivalent of attempting to hire a truck driver and finding out that 90 percent of the job applicants can’t find the gas pedal or the gear shift.

One of the early commenters ascribes this to the Dunning-Kruger Effect.

The Dunning–Kruger effect is a cognitive bias in which “people reach erroneous conclusions and make unfortunate choices but their incompetence robs them of the metacognitive ability to realize it”.[1] The unskilled therefore suffer from illusory superiority, rating their own ability as above average, much higher than in actuality; by contrast the highly skilled underrate their abilities, suffering from illusory inferiority. This leads to a perverse result where less competent people will rate their own ability higher than more competent people. It also explains why actual competence may weaken self-confidence because competent individuals falsely assume that others have an equivalent understanding. “Thus, the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others.”[1]

“ The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt. ”

— Bertrand Russell[2]

The NY Times reported on this study in a 2000 article, Among the Inept, Researchers Discover, Ignorance Is Bliss.

One reason that the ignorant also tend to be the blissfully self-assured, the researchers believe, is that the skills required for competence often are the same skills necessary to recognize competence.

The incompetent, therefore, suffer doubly, they suggested in a paper appearing in the December issue of the Journal of Personality and Social Psychology.

”Not only do they reach erroneous conclusions and make unfortunate choices, but their incompetence robs them of the ability to realize it,” wrote Dr. Kruger, now an assistant professor at the University of Illinois, and Dr. Dunning.

Thanks to David Weiss and This Is True for pointing me to the NY Times article.

I’ve been talking about this study for years now, but didn’t know the effect had a name.  Now I can be extra-geeky when I throw this out in conversation (my preferred paraphrase):

The skills needed to evaluate competence are the same as those required to be competent.  Therefore, if you are incompetent, you don’t know it.

Frankly, that scares me to death.  Dr. Dunning admits the same fear, by the way.

I figure that as long as I am cognizant of this effect and aware of how much more there is to learn,  I’m probably OK.

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