Study finds no impact on student success from having adjunct instructors
Most of the existing research on the employment of adjunct faculty and student success shows a negative relationship, not because adjuncts are bad teachers but because their working conditions prevent them from being as effective as they could be. But earlier this fall, a much-cited study disputed by some, showed the opposite: that students actually may learn more from adjunct faculty members -- at least at research universities that can afford to pay part-timers well and that may discourage tenure-track faculty members from focusing on teaching. Now, a preliminary study is mixing up the literature once again, concluding that employment of adjunct faculty has no impact on student success in community colleges.
“Part-time faculty have no negative impact on student degree or certificate attainment,” reads the study, to be presented today at the Association for the Study of Higher Education annual conference, in St. Louis. “The Effect of Part-time Faculty on Students' Degree and/or Certificate Completion in Two-Year Community Colleges” matches national, individual-level data on student outcomes with national, institutional-level data, including on the percentage of tenure-track and non-tenure-track faculty. Rather, it finds other factors are linked to student success – including college size and location.
“Institution size is negatively associated with students’ chance of degree or certificate completion,” the study says. Those who attend large (10,000 or more students) two-year community colleges are 59 percent less likely to achieve a degree or completion certificate than their peers at smaller community colleges. And those who study in towns, suburbs and cities are 61 percent more likely to complete their programs than their peers at rural colleges.
High school grade-point average also is an indicator of success, with a unit increase in student high school GPA associated with a 14 percent increase in completion rates. ("Unit" increase, as determined by the authors, is about a half a letter grade.)
Hongwei Yu, a postdoctoral research associate at the University of Illinois at Urbana-Champaign’s Office of Community College Research and Leadership, served as the study’s lead author, with assistance from Pilar Mendoza, assistant professor of higher education at the University of Missouri at Columbia, and Dale Campbell, professor of education at the University of Florida.
The authors attribute their findings regarding adjuncts and student success to the possibility that community colleges "hire a significant percentage of part-time faculty who come directly from professional fields and have practical experiences, skills, and knowledge [...] which may help students achieve degree or certificate completion in two-year community colleges. In addition, part-time faculty may provide students connections to workplace or a community."
Yu, a Chinese native, said personal experience inspired the study, which is part of his dissertation. Before coming to the U.S., Yu said, he worked as a part-time instructor of English at a university and technical college, and considered himself to be an effective teacher. So he wanted to more closely examine the role of the adjunct professor on student success at community colleges in this country.
To do so, Yu analyzed individual-level data from the National Center for Education Statistics’ Beginning Postsecondary Students survey alongside a variety of institutional-level data from the national center’s Integrated Postsecondary Education Data System, including the percentage of the faculty that is part-time. (He looked at data on students who enrolled in community colleges in 2003-4 and earned or didn't earn a degree or certificate within three years.). Previous research on adjuncts and student success using individual-level data and institutional-level data only has looked at individual states, making his national picture unique, he said.
Ronald Ehrenberg, director of the Cornell Higher Education Research Institute at Cornell University, is among those whose work has found that when other factors are held constant, the increased use of adjuncts at four-year institutions is associated with lower freshman persistence and graduation rates. The same pattern has been found at two-year institutions, and higher rates of adjunct employment at such colleges have been linked to lower transfer rates to four-year institutions and lower completion rates for associate degrees.
Via email, Ehrenberg called Yu’s methodology “interesting.” Previous studies either have used institutional-level data for dependent and independent variables, such as graduation rates and the share of the faculty that are part-time, or individual-level data, such as persistence to the second year and individual exposure to part-time faculty.
But he pointed to a major limitation of the study, which the authors acknowledge: it only controls for the percentage of the faculty that is part-time, not how much time students spend learning from adjuncts versus their tenure-line colleagues.
Because prior research suggests exposure to part-time faculty plays a role in student success, the study says, "Such information would provide important information regarding the effect of part-time faculty on student’s probability of degree or certificate completion." Of course, at many community colleges, a majority of instruction is provided by those off the tenure track, and so having primarily adjuncts as instructors may be the norm for many students. Another significant limitation to the study is that it doesn't track students who transfer to four-year colleges without earning a degree or certificate, and counts them as dropouts.
Beyond the study's net-zero impact findings regarding adjuncts and students success, Ehrenberg added, all other findings seem consistent with prior studies.
Maria Maisto, president of the New Faculty Majority, a national adjunct advocacy group for adjuncts, said the study would have little impact on the central notion of its campaign for adjunct faculty rights: that faculty working conditions are students’ learning conditions.
“We always say that adjunct faculty can't lose no matter what the research says,” she said. “If students do well as a result of being taught by contingent faculty, then why are these faculty treated so poorly? If students don't do well, then why not improve working conditions to see if student outcomes also improve?”
Many adjuncts and their advocates have said the same in a response to the recent National Bureau of Economic Research study showing Northwestern University students learned more from their non-tenure-line professors than their tenured and tenure-track professors in introductory courses.
Yu said his findings were not the definitive take on adjunct faculty employment, and that colleges shouldn’t use them as a justification for hiring adjuncts under poor conditions. Rather, he said, there’s more research to be done, given the growing portion of the faculty that is part-time.
Administrators should “proceed with caution,” he said. "One of the suggestions I would give is that colleges may have to provide better working conditions [for adjuncts] so that they can promote their performance at community colleges."