On the stability of risk and time preferences amid the COVID-19 pandemic.

We elicited incentivized measures of risk and time preferences from a sample of undergraduate students in Athens, Greece, in waves that preceded and overlapped with the COVID-19 pandemic. We exploited the timing of several events that occurred in the course of the pandemic (e.g., first occurrence of cases and deaths, curfew, relaxation of curfew etc.) and estimated structural parameters for various theories of risk and time preferences comparing these with pre-pandemic estimates. We find no effect between the different waves or other key events of the pandemic, despite the fact that we have about 1000 responses across all waves. Overall, our subjects exhibit intertemporal stability of risk and time preferences despite the significant effect of the COVID-19 pandemic on public health and the global economy. Supplementary Information: The online version contains supplementary material available at 10.1007/s10683-021-09727-6.

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.

Judging statistical models of individual decision making under risk using in- and out-of-sample criteria.

Despite the fact that conceptual models of individual decision making under risk are deterministic, attempts to econometrically estimate risk preferences require some assumption about the stochastic nature of choice. Unfortunately, the consequences of making different assumptions are, at present, unclear. In this paper, we compare three popular error specifications (Fechner, contextual utility, and Luce error) for three different preference functionals (expected utility, rank-dependent utility, and a mixture of those two) using in- and out-of-sample selection criteria. We find drastically different inferences about structural risk preferences across the competing functionals and error specifications. Expected utility theory is least affected by the selection of the error specification. A mixture model combining the two conceptual models assuming contextual utility provides the best fit of the data both in- and out-of-sample.

Food consumption patterns in Mediterranean adolescents: are there differences between overweight and normal-weight adolescents?

OBJECTIVE: To quantify food consumption (based on food group classification) during several time periods in a sample of adolescents and to identify potential differences in food patterns between normal-weight and overweight participants. DESIGN: Cross-sectional study. Participants were classified as normal weight and overweight/obese. Dietary intake was assessed by 3-day food records and analyzed at the food group level for 7 different time periods. To exploit the time dimension of the data and to further control for the influence of other covariates, the authors estimated a random effects regression model for panel data. PARTICIPANTS: One hundred twenty students. SETTING: Two high schools. RESULTS: In multivariate analysis, no statistically significant differences were found between normal-weight and overweight adolescents with regard to their consumption patterns throughout the day. However, compared to females, male participants had higher intake of all food groups with the exception of fruit, and adolescents engaging in vigorous exercise tended to consume more servings from all food groups during any given time period. CONCLUSIONS AND IMPLICATIONS: No preferential use of some food or food groups in specific day periods was found among overweight compared to normal-weight high school students.

Can Mediterranean diet really influence obesity? Evidence from propensity score matching.

Worldwide obesity rates have stimulated interest in healthy dietary patterns. One well-known dietary pattern is the Mediterranean diet, which has been linked with several beneficial health effects. However, concerns have also been raised regarding the Mediterranean diet's role in promoting weight gain. We explored the effect of the Mediterranean diet on body mass index using the propensity score matching approach. We found no statistically significant average treatment effect on the treated and therefore cannot confirm that a causal link exists between Mediterranean diet and body mass index.

A theoretical and empirical investigation of nutritional label use.

Due in part to increasing diet-related health problems caused, among others, by obesity, nutritional labelling has been considered important, mainly because it can provide consumers with information that can be used to make informed and healthier food choices. Several studies have focused on the empirical perspective of nutritional label use. None of these studies, however, have focused on developing a theoretical economic model that would adequately describe nutritional label use based on a utility theoretic framework. We attempt to fill this void by developing a simple theoretical model of nutritional label use, incorporating the time a consumer spends reading labels as part of the food choice process. The demand equations of the model are then empirically tested. Results suggest the significant role of several variables that flow directly from the model which, to our knowledge, have not been used in any previous empirical work.