more on the Dunning-Kruger effect

When incompetent people rate themselves as competent, that's an example of a cognitive bias called the Dunning-Kruger effect. This bias isn't necessarily a function of being smart or stupid; as the video below argues, the effect can be seen across the spectrum in people of both sexes. It could well be that all of us suffer, to some extent, from this bias. I normally tell people, for example, that I'm pretty fluent in French, but that I'm only middling in my Korean-language proficiency. Is this an accurate self-assessment?

A couple years ago, back when R&D was using a language-competency test designed by both me and my now-former boss to determine whom to hire, we had a lady come in to take the test. She proudly claimed, after I had explained that the test would assess her writing ability as well as more technical things like grammatical competence, that "my friends all know me to be a grammar Nazi." So I handed her the test and proctored her for almost an hour. By the end of the test, the woman could no longer even look me in the eye. "Take it," she said dejectedly, handing me the test while staring down at her desk. She ended up scoring a 78%; we had lowered our pass/fail standard from 80% to 70%, so she easily passed. But her self-perception had taken a hit below the waterline, I think. Good. Before and after this lady came to us, we had a slew of linguistic idiots who all thought of themselves as pretty competent. Some of them, despite having seemingly impressive résumés, were too idiotic to understand how poorly they had fared on our test; others, like the unwisely overconfident woman, were fairly rattled by their encounter with reality.

This is why honesty and humility are virtues while egotism and overconfidence are not.