Members of two fraternities have a water fight at UCLA in 1957.Gene Lester / Getty

If everyone strived to embody the core values listed on fraternities’ and sororities’ websites, the world would be a lovely place, full of “true friendship,” “mutual support,” “personal integrity,” and, of course, “scholarship.” The hundreds of thousands of undergraduate students currently in Greek organizations, a new study suggests, could stand to focus a bit more on that last one.

The study, from the economists William Even and Austin Smith of Miami University, in Ohio, examined data on about 34,000 students at a large public university in the Midwest from 2007 to 2017, and found that joining a fraternity or sorority hurt students’ grades. On average, the GPAs of the students who joined the Greek system were 0.1 points lower in the semesters after they joined than what would have been expected based on their grades before. Smith described the effect of joining a fraternity or sorority to me like this: “You can think of it as having all of your professors be worse than average.”

Smith and Even found that the grade drop-off was larger for the students who just barely made the university’s 2.5 GPA cutoff for Greek eligibility. The researchers compared these students to students who fell just under that threshold of 2.5, since all of their GPAs were very close numerically, just on the opposite sides of an arbitrary cutoff. When comparing those two groups’ performance, the researchers calculated that the cost of joining a fraternity or sorority for those with these lower eligible GPAs was an average of about 0.25 points in the semesters after joining. That’s almost the difference between, say, a B and a B- average.

An important distinction is that in Even and Smith’s sample, Greek-affiliated students had GPAs that were an average of between 0.1 and 0.2 points higher than non-Greek-affiliated students’ (which is a bit larger than the advantage that fraternities claim to have nationally). But that likely has more to do with the fact that the university in question required Greek-affiliated students to keep their GPAs above a certain level, and with the types of students who join Greek organizations in the first place—on average they are whiter and come from wealthier families than the students who don’t join. So fraternities and sororities’ members may get better grades, but that doesn’t mean fraternities and sororities make their members’ grades better. Instead, as Even and Smith found, Greek organizations likely make them worse.

The academic downsides of joining a Greek organization were especially large, Even and Smith found, during pledging, when hopefuls undergo “new-member education,” which often includes lots of drinking and sometimes includes hazing. (Even and Smith also noticed that during pledging, students were more likely to pick easier classes.) But in cases where students were suspended from their Greek organization as a result of a disciplinary action, their academic performance actually tended to start improving, in line with what the researchers would’ve predicted had those students not joined in the first place.

Even and Smith’s study didn’t pinpoint what it is about Greek organizations that might hurt their members’ grades (and it’s worth noting that Greek systems at other colleges might have slightly different cultures that could produce different results), but previous research provides a hint. A 2009 study found that Greek-affiliated students drink more than non-Greek-affiliated ones, and other studies have suggested that students’ grades tend to slip if they start drinking more than they did in their earlier college years.

What Greek organizations lose in academics, one could argue, they might make up for in improving their members’ job prospects, perhaps through strong professional alumni networks. Indeed, the students in Even and Smith’s sample tended to make more money—roughly 15 percent more—in their first job after graduation if they’d been in a fraternity or sorority. But that doesn’t mean Greek organizations are themselves the cause of their members’ increased earnings. Students who join the Greek system, Smith told me, tend to have higher-earning, better-educated parents. “And those types of students are probably more likely to have a higher salary early in their careers than those with lower socioeconomic status,” Smith said. After accounting for that, he and Even wrote in the paper that they found “no evidence of a Greek salary premium.”

Students in fraternities and sororities do seem to get better grades and go on to earn more money right out of college—but this research suggests it’s for reasons other than their membership in the Greek system. Their houses may actually be holding them back.

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