Association for Public Policy Analysis & Management

In response to increase in enrollment and decline in budget and state appropriations, many public two-year colleges and open-access four-year colleges accommodate the increased demand by hiring more part-time and fixed-term non-tenure track faculty (Stange et al, 2017; Turner, 2012). While colleges resort to contingent instructors for their lower cost and greater flexibility, some researchers argue that temporary adjuncts may also provide a flexible and low-cost way to screen for effective instructors to be hired on a full-time long-term basis (Autor, 2000).

However, relative little is known whether massive hiring of temporary adjunct instructors truly functions as an effective screening mechanism for more productive instructors. Since the employment of college instructors is a two-way decision making process, where colleges decide whom to retain and adjuncts decide whether they will remain in the teaching position, it is important to examine the whole picture of college faculty employment pattern to understand the policy question on the screening function of adjuncts.

In this study, we examine the following research questions: 1) What are the typical employment patterns among temporary adjunct faculty? 2) Are colleges retaining the most effective adjuncts? 3) Does instructor effectiveness change once they receive long-term employment contract with an institution? To answer these questions, we use a unique administrative data set that links student transcripts with instructor profile with labor market information before and after college employment in both public two-year and four-year institutions in an entire state. In defining instructors’ effectiveness, we build on the existing literature and construct the “value-added” for each instructor by averaging across students’ course grades, and subsequent enrollment and performance in the next course in the same field of study. To address possible student-level and course-level differences, we use a two-way fixed effects model controlling for both instructor fixed effects and course fixed effects.

Preliminary findings indicate that there are high turnover rates among temporary adjunct instructors in both public two-year and four-year colleges. Approximately one quarter of all temporary adjuncts left college for nonteaching positions within one academic year. The most significant predictors for continuing in the college teaching positions beyond the first year include teaching at a younger age, obtaining a terminal degree, and teaching more credits up front. Based on a shrinkage estimator of instructor fixed effects controlling for a wide range of student-level characteristics, we find that both two-year and four-year colleges tend to retain temporary adjunct faculty who have higher value-added in raising students’ current course grades. In contrast, adjuncts who are associated with higher value added on student subsequent course enrollment and performance often are associated with lower value added on student current course grades, and are thus less likely to continue their employment with the college. Finally, among all the adjunct instructors, approximately 10% received longer-term employment. In follow-up analyses, we will examine whether the effectiveness of adjunct instructors who received a long-term contract later improves using an instructor fixed-effect model. Implications for faculty hiring and assessment policies will be discussed during the presentation.