Ronald G. Ehrenberg

Class Size and Student Achievement

Schooling has multiple purposes. In the long run, higher levels of schooling are associated with higher earnings and economic mobility, better health, lower mortality rates, and greater democratic participation. For these reasons, most societies require children to attend school for a specified number of years or until they reach a certain age. Many of the benefits of schooling occur in part because students learn some new knowledge or skills that enhance their ability to communicate, solve problems, and make decisions. Much of the debate over schooling is essentially about how to maximize the amount of student learning, typically as measured by various assessment instruments such as standardized achievement tests. From a societal viewpoint, since resources—most notably, time—are required for learning, and are scarce, the amount of learning needs to be maximized at least cost. Learning is complex, involving cognitive processes that are not completely understood. Typically, school systems have established a primary mode of learning that involves groups of students of about the same age interacting with a single individual leading activities in a confined physical space, directed toward learning a particular topic—in other words, students are placed in classes. The number of other students in the class can vary. At the extreme, there can be one or more adults facilitating learning—teachers—with one or two students. At the other, a student may be one of a few hundred being taught by a single instructor (or, with new Internet technology, one of millions). The number of students in a class has the potential to affect how much is learned in a number of different ways. For example, it could affect how students interact with each other—the level of social engagement. This may result, for example, in more or less noise and disruptive behavior, which in turn affect the kinds of activities the teacher is able to promote. It could affect how much time the teacher is able to focus on individual students and their specific needs rather than on the group as a whole. Since it is easier to focus on one individual in a smaller group, the smaller the class size, the more likely individual attention can be given, in theory at least. The class size could also affect the teacher’s allocation of time and, hence, effectiveness, in other ways, too—for example, how much material can be covered. Teachers may choose different methods of teaching and assessment when they have smaller classes. For example, they may assign more writing, or provide more feedback on students’ written work, or use open-ended assessments, or encourage more discussions, all activities that may be more feasible with a smaller number of students. Exposure to a particular learning environment may affect learning over the time period of exposure, or it may have longer term or delayed effects (e.g., by increasing self-esteem or cognitive developments that have lasting effects). For these reasons, changes to the class size are considered a potential means of changing how much students learn. Not only is class size potentially one of the key variables in the “production” of learning or knowledge, it is one of the simplest variables for policymakers to manipulate. However, the amount of student learning is dependent on many different factors. Some are related to the classroom and school environment in which the class takes place, but others are related to the student’s own background and motivation and broader community influences. When we ask whether class size matters for achievement, it is essential to ask also, how class size matters. This is important for three reasons. First, if we can observe not only achievement differences, but also the mechanisms through which the differences are produced, this will increase our confidence that the differences are real, and not an artifact of some unmeasured or inadequately controlled condition. Second, the effects of class size may vary in different circumstances, and identifying how class size affects achievement will help us to understand why the effects of class size are variable. Third, the potential benefits of class-size reduction may be greater than what we observe. For example, suppose class-size reductions aid achievement, but only when teachers modify instructional practices to take advantage of the smaller classes. If a few teachers make such modifications, but most do not, then understanding how class size affects achievement in some cases will help reveal its potential effects, even if the potential is generally unrealized.

Did teachers' verbal ability and race matter in the 1960s? : Coleman revisited

Abstract Our paper reanalyzes data from the classic 1966 study Equality of Educational Opportunity , or Coleman Report . It addresses whether teacher characteristics, including verbal ability and race, influenced “synthetic gain scores” of students (mean test scores of upper grade students in a school minus mean test scores of lower grade students in a school), in the context of an econometric model that allows for the possibility that teacher characteristics in a school are endogenously determined. We find that verbal aptitude scores of teachers influenced synthetic grain scores for both black and white students. Verbal aptitude mattered as much for black teachers as it did for white teachers. Finally, holding teacher characteristics other than race constant, in some specifications black teachers were associated with higher gain scores for black high school students, but lower gain scores for white elementary and secondary students. Because these findings are for American schools in the mid-1960s, they do not directly apply to our contemporary experience. However, they do raise issues that should be addressed in discussions of hiring policies in American education.

Do Doctoral Students' Financial Support Patterns Affect Their Times-to-Degree and Completion Probabilities

Projections of forthcoming shortages of Ph.D.s abound. Part of the reason is that American college graduates are much less likely to receive doctorates today than thcy were 20 years ago. Two important factors in this decline may be the increase in the length of time necessary for doctorate students to complete their programs that occurred over the period and the low completion rates of entrants into doctoral programs. Among the policies urged to prevent future Ph.D. shortages are increasing support for graduate students. Surprisingly little empirical evidence is available on how different types of support (fellowships. research assistantships, teaching assistantships) are likely to influence times-to-degree and completion rates. Our paper uses data on all graduate students who entered Ph.D. programs in four fields during a 25-year period at a single major doctorate producing university to estimate how graduate student financial support patterns influence these outcomes. We find that completion rates and mean durations of times-to-completion are sensitive to the types of financial support the students received. Other things held constant, students who receive fellowships or research assistantships have higher completion rates and shorter times-to-degree than students who receive teaching assistantships or tuition waivers, or who are totally self-supporting. A major finding Is that the Impact of financial support patterns on the fraction of students who complete programs is much larger than its impact on mean durations of times-to-degree.

Does it pay to attend an elite private college? Evidence on the effects of undergraduate college quality on graduate school attendance

Much attention has recently focused on the rapidly rising costs of a college education, and whether the benefits of attending an elite private college have kept pace with the increasing costs. In this paper we analyze whether undergraduate college quality affects the likelihood that an individual attends graduate school. Using data on three cohorts of students from the National Longitudinal Study of the High School Class of 1972and High School and Beyond , we find that on balance attendance at an elite private college significantly increases the probability of attending graduate school, and more specifically, graduate school at a major research institution. ( JEL I21, J24)

A model of public sector wage determination

Abstract The paper presents an empirical model of wage determination in the public sector that leads to the specification of a system of interrelated wage equations for municipal employees, which allows for occupational and geographic interdependence of wages. The model also considers the influence of public employee unions, municipal government form, and monopsony power of local governments on the wages of municipal employees. Several variants of the derived system of equations are estimated based upon 1967 cross-section data for 478 cities, and the policy implications of the results are discussed.

Reaching for the Brass Ring: The U.S. News & World Report Rankings and Competition

The annual U.S News & World Report ranking of the nations academic institutions exacerbates their competitiveness. Institutions, trying to influence the rankings, alter their behavior in ways that misserve individual students and higher education as a whole. However, institutions should not use the rankings as an excuse for failing to collaborate in ways that make sense both educationally and financially. The paper suggests how USNWR rankings could encourage such collaborations.

The Perfect Storm and the Privatization of Public Higher Education

In this paper the author discusses the various factors which have contributed to a substantial decrease in state funding for public colleges and universities, including increased strain on state tax revenues, rising tuition costs, the discrepancy between public and private institutions in endowment revenues, faculty salaries, and expenditures per student. The author argues that this “perfect storm” of contributing factors threatens the very fabric of the public education system, and paints the dire consequences that could result from the privatization of public education.

Municipal government structure, unionization, and the wages of fire fighters

Determination of the associations among municipal government structure, unionization, and the wages of fire fighters in the United States. Review of related studies; Analysis of the supply and demand factors; Empirical results; Hypothetical framework. (Abstract copyright EBSCO.)

Inside the Black Box of Doctoral Education: What Program Characteristics Influence Doctoral Students' Attrition and Graduation Probabilities?

The Andrew W. Mellon Foundation’s Graduate Education Initiative (GEI) provided funding to 54 departments in the humanities and related social sciences during the 1990s to improve their PhD programs. This article estimates the aspects of PhD programs the GEI influenced and how these aspects influenced attrition and graduation probabilities. It uses survey data on entrants to PhD programs at 44 of the “treatment” departments and 41 “control” departments during a 15-year period that spanned the start of the GEI. Factor analysis is used to group more than 100 program characteristics into a smaller number of factors, and the impact of the GEI on each and the impact of each on attrition and graduation probabilities are estimated. The article estimates the routes via which the GEI influenced attrition and graduation rates and indicates which aspects of PhD programs departments should concentrate on to improve their programs’ performance.

The Sources and Uses of Annual Giving at Selective Private Research Universities and Liberal Arts Colleges.

Abstract Selective private research universities and liberal arts colleges differ in the shares of their annual giving coming from different sources (alumni, other individuals, foundations, corporations) and the shares of their annual giving applied to different uses (current operations, buildings and equipment, enhancing their endowments). After providing background data on the aggregate variation in these shares over time and their variation across institutions at a point in time, our econometric analyses use data from a panels of selective private research universities and liberal arts colleges that span a 31-year period to provide explanations for differences across institutions in the sources and uses of giving. These differences are seen to depend upon a number of institutional characteristics. One key finding is that richer institutions, as measured by endowment per student, devote a larger share of their annual giving to further building their endowments. This contributes to the increasing dispersion of wealth across private academic institutions.