The causal effects of participation in the American Economic Association Summer Minority Program.

• Author: Price, Gregory N.

1. Introduction

   In 1974, the American Economic Association sponsored a Summer Minority Program (hereafter AEASMP). An impetus for the AEASMP was the underrepresentation of racial minorities among the ranks of Ph.D. economists, in addition to the possible shortfalls in academic preparation that, if not addressed, would reduce the likelihood of minorities successfully completing doctoral programs in economics. Thus, from the start and continuing up to the present, the AEASMP provides participants with a curriculum that introduces, and perhaps remediates, core quantitative skills and, in recent years, research skills, essential for completing doctoral programs in economics. (1)

   Given the severe underrepresentation of black Ph.D. economists in the profession, as an intervention, it is conceivable that the AEASMP could have an effect of increasing the likelihood of black participants earning economics doctorates and securing employment as economics faculty. (2) This seems especially plausible if the AEASMP enhances the capabilities of participants and/or cultivates a serious interest in becoming a Ph.D. economist. Notwithstanding such possibilities, nothing is known on the extent to which the AEASMP has causal effects.

   As an intervention, it is of interest to know if the AEASMP has causal effects on outcomes deemed favorable for minority economists. Many outcomes associated with the training of Ph.D. economists are those outcomes associated with placement in tenure-track faculty positions in particular types of academic institutions. Successfully obtaining tenure is also associated with factors such as scholarly productivity, success in securing research resources, and in the prestige associated with scholarly society affiliation. If indeed the AEASMP has causal effects that enhance participants' labor market prospects as academic economists, the AEASMP can be viewed as a successful labormarket intervention.

   This article examines the causal effects of AEASMP participation for minority Ph.D. economists. Methodologically, the treatment effect is identified with an extension of Rubin's (1974) potential outcomes approach. In this framework, there are two outcomes: a treatment state and a control state, and the causal effect of the treatment is simply the difference between the two potential outcomes. Given the nonrandomized nature of the data, differences in attributes between AEASMP participants and nonparticipants could lead to biased estimates of the causal effect of participation.

   Possible bias in estimated treatment effects attributed to differing attributes is, of course, the sample-selection problem. A conventional approach assumes that selection into the treatment is conditioned on both observable and unobservable characteristics, and the treatment effect is estimated with latent variable selection models (Heckman 1979). However, the influential analysis of Lalonde (1986) has cast doubts on the accuracy of such models in estimating treatment effects. In contrast, when selection into the treatment is assumed to be conditioned only on observable characteristics, propensity scoring methods have been demonstrated to replicate experimental benchmarks reasonably well (Dehejia and Wahba, 1998). Below, we use both propensity-score weighted and Heckit estimators to identify and estimate the treatment effects of AEASMP participation. Our estimates of the treatment effects reveal that AEASMP participation has causal and positive effects on research productivity and on the ability to obtain research resources. We find similar effects for both propensity-score weighted and Heckit estimates.

   The remainder of this article is organized as follows. A historical overview of the AEASMP is provided in section 2. Section 3 discusses the data. In section 4, we discuss our methodology--the potential outcomes approach to identifying treatment effects. Given selection on observable characteristics, unobservable characteristics, or both, we motivate the use of propensity-score weighted and Heckit estimators of the treatment effects attributed to AEASMP participation. Section 5 contains the results, where we report on treatment parameter estimates for the average effect of treatment in the population and the average effect of treatment on the treated. The last section concludes.

2. History and Overview of the AEASMP

   The genesis of the AEASMP began in 1969 in the wake of the social and political unrest of the 1960s. (3) Members of the Caucus of Black Economists--the forerunner of the National Economic Association--held conversations with the American Economic Association Executive Board about strategies and programs for black Americans that would enable them to become Ph.D. economists. The impetus for these conversations was plausibly motivated by the severe underrepresentation of blacks among the economics faculty in U.S colleges and universities. Data from the National Science Foundation (NSF) WebCaspar database indicate that, in 1969, no doctorates in economics were awarded to black Americans, and the same was true for the three prior years. (4) This trend continued until 1974, when four doctorates were awarded to black Americans, half of which originated from Howard University--an historically black college/university (HBCU). Such a pattern underscores the anemic pipeline of black Ph.D. economists--the phenomenon of underrepresentation that continues to date (Collins 2000).

   The AEASMP began its official history in 1974, with the University of California-Berkeley as the first host institution. Over the subsequent 29 years, the AEASMP has been hosted by eight additional institutions: Northwestern University (1975-1979), Yale University (1980-1982), University of Wisconsin-Madison (1983-1985), Temple University (1986-1990), Stanford University (1991-1995), University of Texas-Austin (1996-2000), University of Colorado-Denver (2001-2003), and Duke University (2004-present). To date, almost 800 students have participated in the AEASMP. Through 2001, a total of 46 out of 720 former AEASMP participants have gone on to earn doctorates in economics, with some 60 still enrolled in doctoral programs. As of June 2002, participants from the Temple program earned the most doctorates (13), followed by Northwestern (12), Yale (10), Stanford (5), Wisconsin (5), and University of California-Berkeley (1). Twenty-six black American AEASMP alumni were economics faculty members at the end of the 2001-2002 academic year.

   Historically, admission into the AEASMP has been restricted to applicants who have completed at least the sophomore year of college. Admission is also competitive, based primarily on the applicant's grade point average and, according to Leeds (1992), the selectivity of the applicant's undergraduate institution--given that the applicant is at least a sophomore. An exception to the admission criteria occurred when Temple University hosted the AEASMP. Concerned about a possible proskill bias in the admission criteria that would deny opportunities to the most socially disadvantaged racial minorities, the Temple AEASMP reduced both the role of grades and the selectivity of the applicant's undergraduate institution in admission decisions (Leeds 1992). Relative to cohorts that participated in the AEASMP, the Temple experiment does not appear to have had any adverse effects. Participants of the AEASMP at Temple account for the most economics doctorates earned by AEASMP alumni through the year 2001.

   Throughout its history, the central goal of the AEASMP has been to prepare undergraduates from underrepresented racial and ethnic groups for doctoral studies in economics. Presumably, the preparation enabled by the AEASMP would increase the numbers of minorities in the economics profession--a goal of the AEASMP articulated by Leeds (1992). As such, the typical host of the AEASMP provides for participants over a period of approximately eight weeks in the summer, advanced coursework in microeconomics, macroeconomics, and quantitative methods--some combinations of mathematical economics and/or econometrics/statistics. Beginning with the tenure of the University of Colorado-Denver as host in 2001, the curriculum underwent three major innovations. Whereas previous hosts offered one uniform level of instruction, the AEASMP now admits participants in one of two tiers, with two levels of instruction (foundations and advanced). Advanced coursework in macroeconomics has also been replaced with coursework in research methodology and data analysis. It is also possible for an individual to participate in the AEASMP for two summers. Participants that are initially admitted into and complete the foundations part of the program are also eligible to come back as participants in the advanced part of the program.

   Follow-up survey data collected by the AEASMP suggest that it has been reasonably effective at increasing the number of minorities on the economics faculties of colleges/universities. Through the 2000-2001 academic year, some 26 black American and 2 Hispanic AEASMP alumni were economics faculty, which includes at least three faculty in top-ranked economics programs. The AEASMP may have effects on the number of minorities in other professions as well. Follow-up survey data also indicate that, through 2001, some 77 AEASMP alumni earned a Juris doctorate or some other type of doctorate. Of course, such retrospective outcomes do not imply causality, as we cannot observe the counter factual history of an individual had he/she not been an AEASMP participant. Neither do such data allow an inference as to whether or not AEASMP participation effected some capability necessary for success in a given profession--economics faculty or otherwise.

3. Data

   Broadly construed, a treatment effect of program participation is simply an induced change, after participation in a program, in some outcomes. These outcomes can be either be associated with, or interpreted as...