Hmm… Could it be that non-tenured instructors work harder because they know they can be fired?

Scott Jaschik of Inside Higher Ed reports.

The Adjunct Advantage

A major new study has found that new students at Northwestern University learn more when their instructors are adjuncts than when they are tenure-track professors.

The study — released this morning by the National Bureau of Economic Research (abstract available here) — found that the gains are greatest for the students with the weakest academic preparation. And the study found that the gains extended across a wide range of disciplines. The authors of the study suggest that by looking at measures of student learning, and not just course or program completion, their work may provide a significant advance in understanding the impact of non-tenure-track instructors.

Many adjuncts will no doubt be pleased by the study’s conclusions on their teaching ability. But the study does not call for an end to the two-tiered system of academic employment between those on and off the tenure track. Rather, it says that the study may provide evidence that research universities benefit from more teaching by those who don’t have research obligations.

“There are many aspects relating to changes in the tenure status of faculty – from the impact on research productivity to the protection of academic freedom,” the study says. “But certainly learning outcomes are an important consideration in evaluating whether the observed trend away from tenure track/tenured towards non-tenure line faculty is good or bad.

Our results provide evidence that the rise of full-time designated teachers at U.S. colleges and universities may be less of a cause for alarm than some people think, and indeed, may actually be educationally beneficial. Perhaps the growing practice of hiring a combination of research-intensive tenure track faculty members and teaching-intensive lecturers may be an efficient and educationally positive solution to a research university’s multi-tasking problem,” says the paper.