Search Our Scientific Publications & Authors

Am J Agric Econ 2021 May 2;103(3):961-986. Epub 2021 Feb 2.

Department of Nutrition at the University of North Carolina at Chapel Hill and a faculty fellow at Carolina Population Center.

Sugar-sweetened beverage (SSB) taxes have been proposed to discourage excessive sugar consumption, but it is unclear how high- vs. low-SSB purchasers respond to such taxes. We first examine heterogeneity in the purchase and financial effects of a national SSB tax across different types of households buying varying amounts of SSBs. Read More

Am J Agric Econ 2021 Mar 7. Epub 2021 Mar 7.

In this paper, we employ a combination of time regression discontinuity design method (T-RD) and the difference-in-difference method (DID) to identify and quantify the causal effects of the strict lockdown policy on vegetable prices using multiple-year daily price data from 151 wholesale markets of Chinese cabbage. We find that the lockdown policy caused a large and immediate surge in price and price dispersion of Chinese cabbage, though they fluctuated smoothly for the same period in normal years. The DID results further show that the price surge peaked in the fourth week of lockdown but gradually came down to the level of a normal year by week 11. Read More

Am J Agric Econ 2021 Mar 7. Epub 2021 Mar 7.

Much of the attention from COVID-19 has been on the impacts on tourism and other service sectors; but there has been a growing interest in some agricultural and food topics, such as the decline in food away from home (FAFH) expenditures. Our work considers the importance of FAFH in the overall economy, and we also consider changes in agricultural production and trade that have occurred because of COVID-19. We gather data on actual changes to these components, as well as similar shocks to non-agricultural sectors, and employ a simulation model to estimate the impacts on gross domestic product (GDP). Read More

Am J Agric Econ 2021 Feb 23. Epub 2021 Feb 23.

International humanitarian organizations have expressed substantial concern about the potential for increases in food insecurity resulting from the COVID-19 pandemic. We use a unique panel survey of a representative sample households in Addis Ababa to study both food security and food consumption during the pandemic. In contrast to some other countries in the region, Ethiopia never went into a full lockdown severely restricting movement. Read More

Am J Agric Econ 2020 Oct 25. Epub 2020 Oct 25.

This paper looks at the disruption in food supply chains due to COVID-19 induced economic shutdown in India. We use a novel dataset from one of the largest online grocery retailers to look at the impact on product stockouts and prices. We find that product availability falls by 10% for vegetables, fruits, and edible oils, but there is a minimal impact on their prices. Read More

Am J Agric Econ 2019 Oct 26;101(5):1401-1431. Epub 2019 Mar 26.

Associate Vice-President of the Strategy and Knowledge Department International Fund for Agricultural Development (IFAD) Rome, Italy.

Silvio Daidone is a economist and Benjamin Davis is a Strategic Program Leader, both with the Food and Agriculture Organization of the United Nations, Rome, Italy. Sudhanshu Handa is a professor at the University of North Carolina at Chapel Hill. Paul Winters is the Associate Vice-President of the Strategy and Knowledge Department, International Fund for Agricultural Development, Rome, Italy. Read More

Am J Agric Econ 2019 Jan 18;101(1):311-329. Epub 2018 Jun 18.

Scientific Data Analyst, ICF.

We construct panel price indexes using retail scanner data that allow comparisons of consumption cost across space and time. Two types of panel indexes are examined: the rolling-window panel extensions of the multilateral Cave-Christensen-Diewert (CCD) index with the Törnqvist index as its elements, and of the multilateral Gini-Eltetö-Köves-Szulc (GEKS) index using the Fisher ideal index as its elements. The rolling window method maintains the nonrevisability of published index numbers while it allows index numbers for new periods and locations be calculated and the basket of items be updated. Read More

Am J Agric Econ 2019 Feb 21;101(3):753-772. Epub 2019 Feb 21.

African Development Bank (AfDB).

This article addresses the question of whether subsidizing an entirely new agricultural technology for smallholder farmers can aid its adoption early in the diffusion process. Based on a theoretical framework for technology adoption under subjective uncertainty, we implemented a randomized field experiment among 1,200 smallholders in Uganda to estimate the extent to which subsidizing an improved grain storage bag crowds-out or crowds-in commercial buying of the technology. The empirical results show that on average, subsidized households are more likely to buy an additional bag at commercial prices relative to the households with no subsidy who are equally aware of the technology. Read More

Am J Agric Econ 2019 3;101(5):1311-1327. Epub 2019 Sep 3.

International Food Policy Research Institute.

Child dietary diversity is poor in much of rural Africa and developing Asia, prompting significant efforts to leverage agriculture to improve diets. However, growing recognition that even very poor rural households rely on markets to satisfy their demand for nutrient-rich non-staple foods warrants a much better understanding of how rural markets vary in their diversity, competitiveness, frequency and food affordability, and how such characteristics are associated with diets. This article addresses these questions using data from rural Ethiopia. Read More

Am J Agric Econ 2018 Oct 11;100(5):1357-1374. Epub 2018 Sep 11.

Department of Human Sciences, The Ohio State University.

The rise in drug overdose deaths in the United States since the turn of the millennium has been extraordinary. A popular narrative paints a picture whereby opioid overdoses among white, male, less-educated, rural workers have been caused by reduced economic opportunities borne by such people. In this article, we causally test the validity of this theory by using Bartik-type variables to explore the relationship between local economic conditions and county opioid overdose death rates. Read More

Am J Agric Econ 2018 Jul 31;100(5):1302-1319. Epub 2018 Jul 31.

The authors thank seminar participants at the Allied Social Science Association (ASSA) meetings in Philadelphia.

Stunting affects 160 million pre-school children globally with adverse life-long consequences. While work within nutritional science suggests that stunting in early childhood is associated with low intakes of animal-sourced foods (ASFs), this topic has received little attention from economists. We attempt to redress this omission through an analysis of 130,432 children aged 6-23 months from 49 countries. Read More

Am J Agric Econ 2018 Jan;100(1):220-238

Assistant professor in the Environmental and Natural Resource Economics Department at the University of Rhode Island.

We introduce a model that incorporates two important elements to estimating welfare gains from groundwater management: stochasticity and a spatial stock externality. We estimate welfare gains resulting from optimal management under uncertainty as well as a gradual stock externality that produces the dynamics of a large aquifer being slowly exhausted. This groundwater model imposes an important aspect of a depletable natural resource without the extreme assumption of complete exhaustion that is necessary in a traditional single cell (bathtub) model of groundwater extraction. Read More

Am J Agric Econ 2018 13;100(5):1285-1301. Epub 2018 Aug 13.

Policies and programs often aim to improve the affordability of nutritious diets, but existing food price indexes are based on observed quantities that may not meet nutritional goals. To measure changes in the cost of reaching international standards of diet quality, we introduce a new cost of diet diversity index based on the lowest-cost way to include at least five different food groups as defined by the widely used minimum dietary diversity for women (MDD-W) indicator and compare that to a Cost of Nutrient Adequacy indicator for the lowest-cost way to meet estimated average requirements of essential nutrients and dietary energy. We demonstrate application of both indexes using national average monthly prices from two very different sources: an agricultural market information system in Ghana (2009-14) and the data used for national consumer price indexes in Tanzania (2011-15). Read More

Am J Agric Econ 2018 15;100(3):906-930. Epub 2018 Mar 15.

Biofortification is a promising strategy to combat micronutrient malnutrition by promoting the adoption of staple food crops bred to be dense sources of specific micronutrients. Research on biofortified orange-fleshed sweet potato (OFSP) has shown that the crop improves the vitamin A status of children who consume as little as 100 grams per day, and intensive promotion strategies improve dietary intakes of vitamin A in field experiments. However, little is known about OFSP adoption behavior, or about the role that nutrition information plays in promoting adoption and changing diet. Read More

Am J Agric Econ 2017 Aug 16;99(5):1344-1361. Epub 2017 Aug 16.

Brian Dillon is an assistant professor in the Evans School of Public Policy and Governance, University of Washington. Chelsey Dambro is a Global Supply Chain Management Advisor at Catholic Relief Services.

During the structural adjustment era of the 1980s and 1990s, governments across sub-Saharan Africa generally withdrew from crop markets to encourage entry by private traders and foster competition. Since that time, the degree of competition in crop markets has been a central concern of policymakers, donors, and researchers. We review the evidence on that topic by first developing a conceptual framework to guide our analysis, then discussing the findings from four categories of literature. Read More

Am J Agric Econ 2014 Jul;96(4):1070-1083

The obesity epidemic and excessive consumption of sugar-sweetened beverages have led to proposals of economics-based interventions to promote healthy eating in the United States. Targeted food and beverage taxes and subsidies are prominent examples of such potential intervention strategies. This paper examines the differential effects of taxing sugar-sweetened beverages by calories and by ounces on beverage demand. Read More

Am J Agric Econ 2014 Jan;96(1):1-25

U.S. Department of Agriculture, Economic Research Service.

A censored Exact Affine Stone Index incomplete demand system is estimated for 23 packaged foods and beverages and a numéraire good. Instrumental variables are used to control for endogenous prices. A half-cent per ounce increase in sugar-sweetened beverage prices is predicted to reduce total calories from the 23 foods and beverages but increase sodium and fat intakes as a result of product substitution. Read More

Am J Agric Econ 2011;93(4):1082-1098

Economist and research associate at the Urban Institute.

Nearly 15% of all U.S. households and 40% of near-poor households were food insecure in 2009. Read More

Am J Agric Econ 2008 Nov;90(4):951-961

Vitor A. Ozaki and Ricardo Shirota are professors, respectively, in the Department of Exact Sciences and Economics, Business, and Sociology, University of São Paulo; Sujit K. Ghosh and Barry K. Goodwin are full and William Neal Reynolds Distinguished Professor, respectively, in the Department of Statistics and Agricultural and Resource Economics, North Carolina State University.

This article presents a statistical model of agricultural yield data based on a set of hierarchical Bayesian models that allows joint modeling of temporal and spatial autocorrelation. This method captures a comprehensive range of the various uncertainties involved in predicting crop insurance premium rates as opposed to the more traditional ad hoc, two-stage methods that are typically based on independent estimation and prediction. A panel data set of county-average yield data was analyzed for 290 counties in the State of Paraná (Brazil) for the period of 1990 through 2002. Read More

Am J Agric Econ 2003 Dec 1;85(5):1119-1125. Epub 2003 Dec 1.

American Agricultural Economics Association.

Am J Agric Econ 1997 ;79(5):1467-70

Am J Agric Econ 1996 Dec;78(5):1346-8

Am J Agric Econ 1995 Aug;77(3):706-11

Am J Agric Econ 1993 Dec;75(5):1249-53

Am J Agric Econ 1991 Dec;73(5):1440-7

Am J Agric Econ 1991 Dec;73(5):1,334-47

The author analyzes the relationship between population and the environment, with a focus on "the role which environmental degradation and natural resources depletion may play in producing the... Read More

Am J Agric Econ 1990 Dec;72(5):1318-22

Am J Agric Econ 1982 Aug;64(3):444-54

An analysis of the impact of migration to the United States on the sending community and on the labor market in the receiving country is presented based on a case study of Las Animas, Mexico. "As the community becomes increasingly involved in migration, tendencies can be identified regarding changing migration patterns, class differentiation among villagers, impact of migration on village economy, and the changing role of Mexican workers in California labor markets. Results indicate the importance of social networks in determining the outcome of migration; while migration is individually rational, it is a factor of stagnation for village economy, and it helps reproduce segmented California labor markets. Read More

Am J Agric Econ 1982 May;64(2):177-87

Am J Agric Econ 1979 ;61(5):960-6