Michael R. Thomsen

Market Incentives for Safe Foods: An Examination of Shareholder Losses from Meat and Poultry Recalls

Meat and poultry recalls, while voluntary, are carried out under governmental oversight. If firms have financial incentives to avoid being implicated in a recall situation, governmental involvement in recalls may cause firms to internalize social costs when making investment decisions concerning food safety controls. To examine these incentives, we analyze federally supervised meat and poultry recalls from 1982 to 1998 within an event study. Results show significant shareholder losses when publicly traded food companies are implicated in a recall involving serious food safety hazards. We find no evidence that the stock market reacts negatively when recalls involve less severe hazards. Copyright 2001, Oxford University Press.

The effect of fast-food restaurants on childhood obesity: A school level analysis

We analyze, using an instrumental variable approach, the effect of the number of fast-food restaurants on school level obesity rates in Arkansas. Using distance to the nearest major highway as an instrument, our results suggest that exposure to fast-food restaurants can impact weight outcomes. Specifically, we find that the number of fast-food restaurants within a mile from the school can significantly affect school level obesity rates.

Identifying Buyer Market Areas and the Impact of Buyer Concentration in Feeder Cattle Markets Using Mapping and Spatial Statistics

The size and shape of market areas for buyers from four major cattle feeding areas are determined by mapping data from the nations largest video auction. Spatial statistics are also examined to determine their ability to identify market areas for feeder cattle. Mapping shows that procurement areas for feeder cattle buyers are large, irregularly shaped, and overlap substantially. A new statistic was developed to determine primary market areas. Feeder cattle buyers behave as oligopsonists in counties where most buyers are from one feeding area, and prices are higher for feeder cattle in counties where two or more market areas overlap.

LL601 Contamination and Its Impact on U.S. Rice Prices

LL601 is a genetically modified rice variety and unapproved for commercial use. Its presence was found in commercial shipments of U.S. rice in 2006. This article explores its impact on prices and volume marketed for both the United States and Thailand, the major export competitor. The results show a significantly adverse but short duration effect on the U.S. rice market and little to no effect on the Thai rice market.

How do you straddle hogs and pigs? Ask the Greeks!

Evidence of distortions is found in commodity options premiums around informational events. Option Greeks are used to uncover the nature of these distortions in terms of underlying factors. Both changes in underlying futures prices and implied volatility are mispriced.

A Dynamic Decision Model of Technology Adoption under Uncertainty: Case of Herbicide-Resistant Rice

Herbicide-resistant (HR) rice technology is a potential tool for control of red rice in commercial rice production. Using an ex ante mathematical programming framework, this research presents an empirical analysis of HR rice technology adoption under uncertainty. The analysis accounts for stochastic germination of red rice and sheath blight to model a profit maximization problem of crop rotation among HR rice, regular rice, and soybeans. The results demonstrate that risk attitudes and technology efficiency determine adoption rates and optimal rotation patterns.

Food environment and childhood obesity: The effect of dollar stores

In this paper we examine the effect of dollar stores on children’s Body Mass Index (BMI). We use a dataset compiled by the Arkansas Center for Health Improvement that reflects a BMI screening program for public school children in the state of Arkansas. We combine propensity score matching with difference-in-differences methods to deal with time-invariant as well time-varying unobserved factors. We find no evidence that the presence of dollar stores within a reasonably close proximity of the child’s residence increases BMI. In fact, we see an increase in BMI when dollar stores leave a child’s neighborhood. Given the proliferation of dollar stores in rural and low-income urban areas, the question of whether dollar stores are contributing to high rates of childhood obesity is policy relevant. However, our results provide some evidence that exposure to dollar stores is not a causal factor.

Persistent disparities in obesity risk among public schoolchildren from childhood through adolescence.

INTRODUCTION Arkansas is among the poorest states and has high rates of childhood obesity. In 2003, it became the first state to systematically screen public schoolchildren for unhealthy weight status. This study aims to examine the socioeconomic disparities in Body Mass Index (BMI) growth and the risk of the onset of obesity from childhood through adolescence. METHODS This study analyzed (in 2015) the data for a large cohort of Arkansas public schoolchildren for whom BMIs were measured from school years 2003/2004 through 2009/2010. A linear growth curve model was used to assess how child-level sociodemographics and neighborhood characteristics were associated with growth in BMI z-scores. Cox regression was subsequently used to investigate how these factors were associated with the onset of obesity. Because children might be classified as obese in multiple years, sensitivity analysis was conducted using recurrent event Cox regression. RESULTS Survival analysis indicated that the risk of onset of obesity rose sharply between ages of 5 and 10 and then again after age 15. The socioeconomic disparities in obesity risk persisted from kindergarten through adolescence. While better access to full service restaurants was associated with lower risk of the onset of obesity (Hazard Ratio (HR)=0.98, 95% CI=0.97-0.99), proximity to fast food restaurants was related to increased risk of the onset of obesity (HR=1.01, 95% CI=1.00-1.01). CONCLUSIONS This analysis stresses the need for policies to narrow the socioeconomic gradient and identifies important time periods for preventative interventions in childhood obesity.

Do peers affect childhood obesity outcomes? Peer-effect analysis in public schools

This study investigates whether obese peers are a contributing factor in childhood body-weight outcomes. Using an instrumental variables method on exogenously assigned peers (i.e., new peers), we find that the weight of peers within the same grade and school significantly impacts body mass index (BMI) z-score of an individual student. The size of the peer effect, however, is negligible. We find no evidence of interaction between newly assigned peer groups prior to assignment. Furthermore, the obese peers variable is significant only for those peers with whom a student interacts.

The Effect of Neighborhood Fast Food on Children’s BMI: Evidence from a Sample of Movers

Abstract We use a statewide panel dataset and an instrumental variable strategy to identify the effect of neighborhood fast food on the BMI z-scores of Arkansas public schoolchildren. As in earlier studies, we use distance from the child’s residence to the nearest major highway as an instrument for the density of fast-food restaurants. The sample is limited to children who moved at least once during the study period to ensure temporal variation in our instrument. Neighborhood fast food does have significant and positive effects on their BMI z-scores. The effect is disproportionately large for children who are rural, non-minority and female.