Jonathan Klick

Strong Claims and Weak Evidence: Reassessing the Predictive Validity of the IAT

The authors reanalyzed data from 2 influential studies-A. R. McConnell and J. M. Leibold and J. C. Ziegert and P. J. Hanges-that explore links between implicit bias and discriminatory behavior and that have been invoked to support strong claims about the predictive validity of the Implicit Association Test. In both of these studies, the inclusion of race Implicit Association Test scores in regression models reduced prediction errors by only tiny amounts, and Implicit Association Test scores did not permit prediction of individual-level behaviors. Furthermore, the results were not robust when the impact of rater reliability, statistical specifications, and/or outliers were taken into account, and reanalysis of A. R. McConnell & J. M. Leibold (2001) revealed a pattern of behavior consistent with a pro-Black behavioral bias, rather than the anti-Black bias suggested in the original study.

Medical Malpractice Reform and Physicians in High-Risk Specialties

If medical malpractice reform affects the supply of physicians, the effects will be concentrated in specialties facing high liability exposure. Many doctors are likely to be indifferent regarding reform, because their likelihood of being sued is low. This difference can be exploited to isolate the causal effect of medical malpractice reform on the supply of doctors in high-risk specialties, by using doctors in low-risk specialties as a contemporaneous within-state control group. Using this triple-differences design to control for unobserved effects that correlate with the passage of medical malpractice reform, we show that only caps on noneconomic damages have a statistically significant effect on the per capita number of doctors and that this effect is concentrated among only those specialties that face the highest litigation exposure. (c) 2007 by The University of Chicago. All rights reserved.Many states have passed medical malpractice law reforms in an effort to retain and attract physicians. However, it is unclear what the net public health effect of such reforms is. While reforms are likely to help states retain doctors, they also diminish incentives to provide a high level of health care. We provide empirical evidence that some malpractice reforms have helped states retain doctors while others have not. However, retention of doctors comes at a cost. We show that some malpractice law reforms have lowered the level of care provided, as indicated by an increase in infant mortality. This suggests that some of the tort reforms lead to worsening health outcomes. JEL Classifications: I11, I12, I18, K13, K32, D00

Cheap Donuts and Expensive Broccoli: The Effect of Relative Prices on Obesity

In recent years, much attention has been directed at the ongoing increase in body weight, and what might be done about it. We use data from the National Health Interview Survey (NHIS) for the period 1982-1996 to estimate models relating measures of body weight (BMI, a dummy indicating that a person is overweight or obese, and a dummy indicating that a person is obese) to two food price indexes constructed using regional BLS price data as well as the official BLS food price index. The most aggressive use of our results suggests that variation in year-to-year food prices is unlikely to explain much of the increase in body weight over our sample period. This conclusion holds true regardless of the food price measure we consider.

Diabetes Treatments and Moral Hazard

In the face of rising rates of diabetes, many states have passed laws requiring health insurance plans to cover medical treatments for the disease. Although supporters of the mandates expect them to improve the health of diabetics, the mandates have the potential to generate a moral hazard to the extent that medical treatments might displace individual behavioral improvements. Another possibility is that the mandates do little to improve insurance coverage for most individuals, as previous research on benefit mandates has suggested that mandates often duplicate what plans already cover. To examine the effects of these mandates, we employ a triple‐differences methodology comparing the change in the gap in body mass index (BMI) between diabetics and nondiabetics in mandate and nonmandate states. We find that mandates do generate a moral hazard problem, with diabetics exhibiting higher BMIs after the adoption of these mandates.

The Effect of Abortion Legalization on Sexual Behavior: Evidence from Sexually Transmitted Diseases

Unwanted pregnancy represents a major cost of sexual activity. When abortion was legalized in a number of states in 1969 and 1970 (and nationally in 1973), this cost was reduced. We predict that abortion legalization generated incentives leading to an increase in sexual activity, accompanied by an increase in sexually transmitted diseases (STDs). Using Centers for Disease Control data on the incidence of gonorrhea and syphilis by state, we test the hypothesis that abortion legalization led to an increase in sexually transmitted diseases. We find that gonorrhea and syphilis incidences are significantly and positively correlated with abortion legalization. Further, we find a divergence in STD rates among early legalizing states and late legalizing states starting in 1970 and a subsequent convergence after the Roe v. Wade decision, indicating that the relation between STDs and abortion is causal. Abortion legalization accounts for about one‐fourth of the average disease incidence.

Valid Inference in Single-Firm, Single-Event Studies

Single-firm event studies play an important role in both scholarship and litigation despite the general invalidity of standard inference. We use a broad cross-section of 2000--2007 CRSP data and find that the standard approach performs poorly in terms of both Type I and Type II error rates. We discuss a simple-to-use alternative, the SQ test, based on sample quantiles of the empirical distribution of pre-event fitted excess returns, which has correct asymptotic Type I error rate. Results suggest that the test will be useful in studying the impact of firm-specific events such as regulation, anti-trust rulings, and corporate or securities litigation. Copyright 2013, Oxford University Press.

The Effect of Abortion Liberalization on Sexual Behavior: International Evidence

Most industrialized countries have increased access to abortion over the past 30 years. Economic theory predicts that abortion laws affect sexual behavior since they change the marginal cost of having risky sex. We use gonorrhea incidence as a metric of risky sexual behavior. Using a panel of 41 North American, European and Central Asian countries over the period 1980-2000, we estimate the impact of abortion law reform on risky sex. Compared to the most restrictive legislation that permits abortion only to save the pregnant woman’s life or her physical health, more liberal abortion laws are associated with at least thirty additional gonorrhea cases per 100,000 individuals. The marginal effect of laws which make abortion available on request is larger than the effect of laws which allow abortion on socioeconomic and mental health grounds. Our results are robust against a set of alternative sample constructions and model specifications.

Data Watch: Tort-uring the Data

This article discusses data available for researchers interested in the U.S. civil justice system and illustrates the uses of the various datasets with some interesting findings. Our focus is on torts, defined as an injury to person or property that is not covered by contract and for which civil liability may be imposed. The most common tort is the result of an auto accident. We discuss data useful for analyzing trends, data that are useful for cross-sectional research and finally data covering only a specific type of civil litigation such as medical malpractice. We conclude by discussing the limitations of all civil litigation data.

Subsidizing Addiction: Do State Health Insurance Mandates Increase Alcohol Consumption?

A model of addiction in which individuals are forward looking implies that as the availability of addiction treatment options grows, individuals will consume more of an addictive good. We test this implication using cross-state variation in the adoption of mental health parity mandates that include substance abuse treatments. We examine the effects of these mandates on the consumption of alcohol and find that parity legislation leads to an increase in alcohol consumption. To account for the possible endogeneity of the adoption of mental health parity mandates, we perform an instrumental variables analysis and find that the ordinary least squares estimation significantly underestimates the insurance effect on alcohol consumption.

The Institutes of Medicine Report: Too Quick to Diagnose Bias

The Institute of Medicine report, Unequal Treatment: Confronting Racial and Ethnic Disparities in Health Care, claims that medical studies document a systematic causal relationship between race and disparities in health inputs and outcomes among individuals of different races. This article argues that the majority of studies are not powerful enough to establish a causal link, since they do not sufficiently control for differences among patients that happen to correlate with race, and it outlines a powerful audit study that could isolate any effect of race on health care decisions. Even if there are race-based disparities in health inputs, evaluations of welfare and policy prescriptions should be based on health outcomes, since the relationship between care and health is, at least in some cases, weak.