By now, the secret is out in some disciplines: if you want to land a tenure-line faculty job, you’d better attend a highly ranked graduate program -- not necessarily because they’re better but because the market favors prestige. But a new study suggests that “social inequality” might be worse than previously thought, across a range of different disciplines.

The study, published this week in Science Advances, is based on hand-curated data about placements of 19,000 tenure-line faculty members in history, business and computer science at 461 North American institutions with doctoral programs. Using a computer-aided, network-style analysis, the authors determined that just 25 percent of those institutions produced 71 to 86 percent of tenure-line professors, depending on discipline.

Using the Gini coefficient, a standard measure of social inequality, the authors found there’s extreme elitism even at the top of that quartile. The top 10 programs in each discipline produce 1.6 to 3 times more faculty than even the next 10 programs in the ranking. And the top 11 to 20 programs produce 2.3 to 5.6 times more professors than the next 10 programs.

“For such differences to reflect purely meritocratic outcomes, that is, utilitarian optimality of total scholarship, differences in placement rates must reflect inherent differences in the production of scholarship,” the study says. “Under a meritocracy, the observed placement rates would imply that faculty with doctorates from the top 10 units are inherently 2 to 6 times more productive than faculty with doctorates from the third 10 units.”

The magnitude of such differences make a pure meritocracy “implausible,” the report says, “suggesting the influence of nonmeritocratic factors like social status.”

Aaron Clauset, an assistant professor of computer science at the University of Colorado at Boulder, led the study, which is called “Systematic Inequality and Hierarchy in Faculty Hiring Networks.” His coauthors are Samuel Arbesman, a senior adjunct fellow at the Silicon Flatirons Center for Law, Technology and Entrepreneurship at Colorado, and Daniel B. Larremore, a postdoctoral fellow at the Harvard School of Public Health.

Clauset said that when someone is working within a meritocracy, he or she has about an even (50 percent) chance of being placed in a higher-ranked or lower-ranked program than his or her Ph.D. program. But across disciplines, the study reveals steep “prestige hierarchies,” he said, in which only about 9 to 14 percent of Ph.D.s get a job in a more highly ranked program then their own. Placement figures for women in elite programs are slightly worse.

Across the disciplines, the paper says, Ph.D.s place at institutions that average 27 to 47 ranks below their doctorate-granting institutions. And those are just for faculty members who get tenure-track jobs within the institutional data set; adjuncts and Ph.D.s who are employed outside ranked institutions didn’t make it into the study.

The study doesn’t rely on outside rankings, such as those from U.S. News & World Report. Rather, it generates its own ranking system based on placements. Because the departments with the best placement records tend to hire faculty from like institutions, it creates a kind of “small world” effect, the report says. An interactive graphic Larremore created is available here.

Other studies have shown the same hiring tendencies in other disciplines. A study published earlier this year, for example, said that of those English Ph.D.s graduating from the top 6 programs in their field (as rated by U.S. News & World Report), 12.4 percent land jobs at universities whose graduate programs are ranked among the top 28. For those in the bottom half of all doctoral programs (who collectively make up nearly half of new English Ph.D.s), only 0.21 percent land jobs at those same 28 universities. Another study, from 2012, looked at political science Ph.D.s from 116 universities ranked by U.S. News and found that about 20 percent of political science professors in all programs graduated from the top 4 programs: Harvard, Princeton and Stanford Universities and the University of Michigan. The top 11 institutions were collectively responsible for the doctoral education of about half of those in tenured or tenure-track positions at all ranked institutions, leaving more than 100 departments to "contest the remaining 50 percent of openings.”

Clauset said he thought his study built on the existing literature by showing this phenomenon across a range of very different disciplines -- suggesting it happens across academe.

Karen Kelsky, a former academic who advises graduate students and Ph.D.s on the academic job market and runs the blog The Professor Is In, said the findings were “absolutely” in line with what she observes every day in her work.

“[My] clients and readers from the most elite institutions have the easiest time getting jobs,” she said -- with the disclaimer that not all Ph.D.s from elite institutions get increasingly rare tenure-line jobs, and that many are working as adjuncts or contemplating leaving academe. “But of the clients with whom I've worked who do sail quickly and relatively painlessly into tenure-track jobs, the majority are from elite programs.”

For that reason, she said, she started sending out a default message to anyone writing her for advice about whether or not to get a Ph.D., which reads, in part: "Go only to an elite or high-ranking program, and take on absolutely no debt to do the entire program start to finish. If all those are possible and you are under 40, then it's not a bad choice. …I know this is discouraging, but it is based on my knowledge of the terrible financial hardship faced by most Ph.D.s, especially in the humanities, at this point in time."

Robert Oprisko, a political scientist and research scholar at Indiana University, wrote the 2012 paper on placement in political science. He said Clauset’s study offers valuable data and analysis, particularly in that faculty placement is a better measure of a program’s performance than the input-based criteria on which other ranking systems, such as U.S. News, are based. But the study lacks some of the discussion and context that could add to its value, he said. (Clauset and his coauthors pose a few questions about the impact of hiring practices on academe, such as “How many meritorious research careers are derailed by the faculty job market’s preference for prestigious doctorates?” and “Would academia be better off, in terms of collective scholarship, with a narrower gap in placement rates?” But they don’t offer answers, mainly calling for additional study.)

Oprisko pointed to another study, published last year in the Journal of Economic Perspectives, which said that while the top Ph.D. students from the highest-ranked economics departments tend to be extremely productive scholars in the first six years of their careers, the rest of their cohorts are pretty unproductive. The lesson? Picking faculty candidates by department prestige alone doesn’t mean they’ll be good professors or researchers.

Ideally, Oprisko said, faculty members would be hired based on their productivity. But when faced with a mountain of applications, including those from candidates who are still working on their dissertations, search committees probably rely on institutional prestige as an indicator of quality more than they should, he said. Coupled with the professoriate’s tendency to “remake” the next generation of scholars in its own mold, it’s something of a perfect storm, he said.

“The key here is to show that the merit ‘veneer’ doesn’t hold at all,” he said. “The way we’re choosing placement is ridiculous -- it has nothing to do with merit and it’s all about social status.”

Clauset said he didn’t think the study should frighten would-be professors away from their goals. But he said he thought it was important information for anyone considering the profession.

“I don’t think that if I had seen this study in graduate school it would have deterred me from this path to becoming a professor,” he said. “But knowing how steep the mountain is can help people make decisions about whether or not they want to climb it.”