And even in college and grad school, we give (and get) points for extroversion.

FORBES: You Don't Have To Be Loud to Lead

As he predicted, people whose scores put them in between extreme extroversion and introversion turned out to be the best salespeople.

FORBES: Move Over Extroverts, Here Come the Ambiverts

And passionate, the attribute that people most associate with extroversion, is actually about depth of commitment: you can be quietly, deeply passionate.

FORBES: You Don't Have To Be Loud to Lead

Stillwell says companies are already using these kinds of machine-learning models to make connections, though the companies may not know that they're measuring IQ or extroversion.

CNN: Heather Kelly,

Each possessed a different level of extroversion and friendliness.

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