Previous studies have shown that papers with a diverse set of authors are cited more often and produce higher-impact discoveries. That makes sense—different people with different life experiences bring different ideas to the table. It’s hard for new ideas and research to emerge if the opportunities are not present.
However, according to new research, this is happening in academia, where 80% of all domestically trained faculty are from just 20% of universities. That means just five U.S. universities have trained 1-in-8 tenure-track faculty members serving at the nation’s institutions of higher learning.
The study, published in Nature, takes the most exhaustive look yet at the structure of the American professoriate—capturing data on nearly 300,000 tenure-track faculty at more than 10,000 university departments at 368 PhD-granting institutions from 2011 to 2020.
The findings reveal that in all fields of academia, most professors come from a small number of institutions.
The authors, all University of Colorado Boulder professors, find that the issue lies in ubiquitous hierarchies of prestige throughout academia. For example, academics who earned their degrees at less prestigious schools rarely gain employment at more prestigious institutions. In computer science, only 12% of faculty were able to get jobs at universities more prestigious than where they went to school—a number that plummeted to 6% in economics.
“Treating the flows of faculty between U.S. universities as a network leads to a natural, recursive definition of prestige: a department is prestigious if its graduates are hired by other prestigious departments,” write the authors.
According to the study, the five most common doctoral training universities—UC Berkeley, Harvard, University of Michigan, University of Wisconsin-Madison and Stanford—account for just over one in eight domestically trained faculty. That pattern persists across field-level top 10 departments, as well.
Among the 1,070 departments that are ranked top-10 in any field, 248 (23%) top-10 slots are occupied by departments at four of those five universities—UC Berkeley, Harvard, University of Wisconsin-Madison, Stanford and Columbia. Almost three-quarters of the 252 universities—64%—have zero top-10 departments.
“These findings show that, both within individual fields and across entire domains, faculty placement power is highly concentrated among a small set of universities, complementing the already enormous concentration of faculty production among the same set of universities,” explain the authors. “Together, these patterns create network structures characterized by a closely connected core of high-prestige universities that exchange faculty with each other and export faculty to—but rarely import them from—universities in the network periphery.”
Additionally, the study shows universities that employ more faculty generally also place more of their graduates as faculty elsewhere.
The picture the study data paints for faculty hiring does not look better for women. Whereas women’s overall representation has increased across all eight broad domains of study, they are still underrepresented in many fields, especially STEM.
The researchers discovered that women’s representation among newly hired faculty over the past decade has generally been flat. As a result, the continued increase in women’s overall representation can instead be attributed to the disproportionate number of men among retiring faculty. Thus, continued increases in women’s representation among faculty are unlikely.
“We should not expect to see gender parity in academia, unless further initiatives and changes in hiring practices are made,” said Hunter Wapman, lead author of the paper and a doctoral student in the Department of Computer Science.
Lastly, the Wapman and his colleagues found that 1 in 11 U.S. professors are employed by their doctoral university, a practice called “self-hiring.”
“Elevated self-hiring rates may indicate an unhealthy academic system because self-hiring restricts the spread of ideas and expertise, and many decades of study suggest that it can correlate with lower quantity and quality of scholarship,” conclude the study authors.