STRENGTHENING THE REGRESSION DISCONTINUITY DESIGN USING ADDITIONAL DESIGN ELEMENTS: A WITHIN‐STUDY COMPARISON

The sharp regression discontinuity design (RDD) has three key weaknesses compared to the randomized clinical trial (RCT). It has lower statistical power, it is more dependent on statistical modeling assumptions, and its treatment effect estimates are limited to the narrow subpopulation of cases immediately around the cutoff, which is rarely of direct scientific or policy interest. This paper examines how adding an untreated comparison to the basic RDD structure can mitigate these three problems. In the example we present, pretest observations on the posttest outcome measure are used to form a comparison RDD function. To assess its performance as a supplement to the basic RDD, we designed a within‐study comparison that compares causal estimates and their standard errors for (1) the basic posttest‐only RDD, (2) a pretest‐supplemented RDD, and (3) an RCT chosen to serve as the causal benchmark. The two RDD designs are constructed from the RCT, and all analyses are replicated with three different assignment cutoffs in three American states. The results show that adding the pretest makes functional form assumptions more transparent. It also produces causal estimates that are more precise than in the posttest‐only RDD, but that are nonetheless larger than in the RCT. Neither RDD version shows much bias at the cutoff, and the pretest‐supplemented RDD produces causal effects in the region beyond the cutoff that are very similar to the RCT estimates for that same region. Thus, the pretest‐supplemented RDD improves on the standard RDD in multiple ways that bring causal estimates and their standard errors closer to those of an RCT, not just at the cutoff, but also away from it.     

"PUBLICITY" AS A PROBLEM IN THE INTERNAL VALIDITY OF TIME SERIES QUASI-EXPERIMENTS

Scholars who work with time series quasi-experiments have identified "publicity" as a problem in the interpretation of such research designs. The present study utilizes three examples of the role of publicity in three social interventions: the Romanian abortion restriction of 1966; the British breathalyzer crackdown; and, the 1978 Georgia Status Offender Act. The authors conclude that publicity is most likely to be a problem in internal validity when (1) the intervention is not truly abrupt and (2) a broad "policy" is evaluated as opposed to a "program."     

THE COURTS AS A SOURCE OF REGULATORY REVITALIZATION: EXTERNAL AGENDA SETTING AND EQUAL EDUCATION PROGRAMS

The authors examine the relationship between the courts and HEW's Office for Civil Rights (OCR), to illustrate the effects of legal efforts to generate more vigorous agency enforcement. Opponents of racial and sex discrimination in public schools won a series of suits against OCR after it had ceased to effectively implement anti-discrimination legislation. As a result of court decisions, OCR has had its discretion over how it will carry out its legislative responsibilities curtailed.     

MEDICAL ANTHROPOLOGY HEALTH POLICY AND THE STATE: A CASE STUDY OF SUDAN

Medical anthropologists have frequently limited themselves to studying cultural factors in illness, curing or resistance to the acceptance of modern Western medical services. This prevailing "socioculturalist" approach has serious analytical shortcomings resulting from underestimating the importance of the social formations in which cultural factors occur. Consequently, the policy recommendations produced in medical anthropology are often crippled by theoretical limitations. It is argued that the historically specific constellation of social relations governing production and the appropriation and distribution of the economic surplus-commonly embodied in the functions of the state-have profound effects on the pattern of health and illness as well as on the availability of health services. In underdeveloped countries an analysis of the role of the state in health is especially important, since the organs of state power play a stronger role in health care than in countries with well developed markets for medical services.
In the case of Sudan, the interests of the state in colonial and postindependence periods required a development strategy involving large-scale irrigated agriculture utilizing seasonal migrant labor. The labor and health policies aimed at economic productivity and political stability are analyzed here in relation to the adverse health effects and serious maldistribution of health services which resulted.     

SPEED KILLS: A LONGITUDINAL ANALYSIS OF TRAFFIC FATALITIES AND THE 55 MPH SPEED LIMIT*

An interrupted time-series design is used to analyze the impact of the 55 mph speed limit on U.S. traffic fatalities over the period 1950 to 1980. In addition to speed such potential effects on highway fatalities as safety improvements, decreased speed dispersion, and decreased travel are examined. We conclude that the overwhelming proportion of the decline in traffic fatalities from 1973 to 1974 must be attributed to the change in the speed limit.     

A DESIGN PERSPECTIVE ON POLICY IMPLEMENTATION: THE FALLACIES OF MISPLACED PRESCRIPTION

Implementation has been used to try to explain too much, particularly that policy formulation should be oriented around implementation. The concentration on implementation has added little to our theoretical understanding of policymaking. Implementation studies have taken either "The Horrors of War" or "The Search for Theory" views. The latter has four major views, none of which is adequate. The best approach is to treat implementation as only one of a number of conditions which must be fulfilled for successful policymaking. The design perspection, explained in the paper, is the best approach for this.     

EVALUATING TVA: THE CONTRIBUTION OF ECONOMIC. HISTORICAL. AND ADMINISTRATIVE ANALYSIS

William U. Chandler. The Myth of TVA: Conservation and Development in the Tennessee Valley, 1933–1983
Robert F. Durant. When Government Regulates Itself: EPA, E V A, and Pollution Control in the 1970s
Erwin C. Hargrove and Paul K. Conkin, eds. TVA: Fifty Years of Grossroofs Bureaucracy