Social organizations have long been a part of the student experience at colleges and universities in the United States.

　　Fraternities and sororities have been a major part of the experience for so long it is almost hard to imagine U.S. higher education without them.

　　Many Americans use the term Greek life for fraternities and sororities because their names come from letters in the Greek language. Taking part in such groups does cost money. But there are many reasons students join them.

　　At many U.S. colleges and universities, fraternities and sororities provide housing for students. They also help students make new friends and personal connections, both in and out of school. Some of these organizations were set up mainly for a given field of study, religion or other activity, such as musical performance.

　　Most Greek Life groups expect members to get involved with their community through service. But there also is a culture of partying, drinking alcohol, and even bad behavior among some of the groups.

　　One way Greek organizations try to demonstrate their value to students is by suggesting that joining improves members' academic performance and earnings after college. So a team of U.S. researchers decided to look at how Greek life affected students in those areas.

　　Alpha Chi Omega's new member, Ella Finley's, right, hugs her

　　Alpha Chi Omega's new member, Ella Finley's, right, hugs her "big sis" Kaytlyn Carlson, left, during the University of Alabama sorority Bid Day, Saturday, August 19, 2017, in Tuscaloosa, Alabama.

　　Looking to the effect on studies and earnings

　　The researchers are with Miami University in Oxford, Ohio. They looked at the academic performance of over 34,100 students at a large, unnamed pubic university over a 10-year period. They also looked at how much money the former students of that school earned.

　　The researchers released their findings through the publishing service SSRN last October.

　　Almost every college and university with fraternities and sororities sets academic requirements for their members. To take part in Greek life, students must keep their grade point average, or GPA, at or above a given level. At the university in the study, the lowest level of GPA a Greek life member can have is 2.5 out of a possible 4.0.

　　The school in the study does not let its students join fraternities and sororities until the second half of their first year. So the researchers were able to compare the students' GPAs before and after they joined Greek life. They found that, on average, the GPAs of Greek life members fell by about 0.25 points after they joined.

　　Academic performance was a problem especially during a period known as rush, the researchers noted. Before letting a student become a member, he or she is required to complete difficult tasks during rush, often involving alcohol. The researchers found that this was a period when students dropped out of classes or more often chose to take easier ones.

　　William Even is a professor of economics at Miami University and the lead researcher in the study. He says the decrease in academic performance among Greek life members was greater than among students who started college at the same time, but chose not to join.

　　"Bottom line: our study shows that the simple statistics on GPA paint a false picture of how joining a [fraternity or sorority] affects grades," Even wrote in a message to VOA. "Closer inspection reveals negative effects.

　　Even said the study found no evidence that being a member of one of these groups improves a student's earnings after college, as some Greek organizations claim.

　　In defense of Greek life

　　The North American Interfraternity Conference and the National Panhellenic Conference are the two biggest supporters of Greek Life in the country. Leaders from the two groups released a joint statement through the Chronicle of Higher Education after the findings were released.

　　The leaders stated that they were pleased the researchers looked at the issues of academic performance among Greek life members. But they also noted the researchers looked only at one school.

　　"A host of studies show membership contributes to a students' sense of community and belonging on campus, which provides a greater sense of attachment to a university," they wrote.

　　The Greek organizations' leaders pointed to two other studies. One study was done by the Association of Fraternity Advisors in 2006. It found that fraternity members are 20 percent more likely to successfully complete their studies than non-members. The other study, from 2014, looked at sorority members. It found that they are 11 percent more likely to stay with their study programs between the first and second years in college, a point when many students leave.

　　In addition, there are things that being part of Greek life teaches students that they do not necessarily get in the classroom, says Roberto Angulo. He helped to create AfterCollege, an internet-based service that helps students find the best possible jobs for their skill sets after they complete their college studies. He was also a member of the Kappa Alpha fraternity while attending Stanford University in the mid-1990s.

　　Angulo notes that many companies do want workers who are highly knowledgeable of the areas in which they work. But he argues they also want job candidates with more general skills, like leadership and the ability to work well with others.

　　Membership in Greek organizations demonstrates these qualities through the many community service projects in which they are involved.

　　Employers who were once members of a Greek group themselves are more likely to employ fellow members, Angulo says. And, the social skills one gains from involvement are also helpful in fields like business and sales, he adds. Also, they can be very useful when an individual wants to progress in his or her career path.

　　"If you want to get a raise ... it's not so much based on your GPA," said Angulo. "It's how willing you are to ask for that extra package when you start or how actively you negotiate your offers."

　　Still, fraternities and sororities have other issues affecting the way the public looks at them. These issues include reports of alcohol abuse, physical and verbal abuse of membership candidates, and sexual violence. Some groups have been named in police investigations and even court cases.

　　I'm ­Pete Musto.

　　And I'm Dorothy Gundy.

　　Pete Musto reported this story for VOA Learning English. George Grow was the editor.

　　We want to hear from you. How common are college student social organizations in your country? What affect do you think they have on student performance? Write to us in the Comments Section or on 51VOA.COM.