It’s also abundantly, poignantly clear that during puberty, kids have absolutely no clue how to assess character or read the behavior of others. In 2005, the sociologist Koji Ueno looked at one of the largest samples of adolescents in the United States, and found that only 37 percent of their friendships were reciprocal—meaning that when respondents were asked to name their closest friends, the results were mutual only 37 percent of the time. One could argue that this heartbreaking statistic is just further proof that high school is a time of unrequited longings. But these statistics also suggest that teenagers cannot tell when they are being rejected (Hey, guys, wait for me!) or even accepted (I thought you hated me). So much of what they think they know about others’ opinions of them is plain wrong. —New York Magazine.

That was 2005, before the Facebook wave quantified and publicized social relationships that had before been left largely implicit.