Agricultural & Applied Economics Association

Agricultural lands occupy 37% of the earth's land surface. Agriculture accounts for 52 and 84% of global anthropogenic methane and nitrous oxide emissions. Agricultural soils may also act as a sink or source for CO2, but the net flux is small. Many agricultural practices can potentially mitigate greenhouse gas (GHG) emissions, the most prominent of which are improved cropland and grazing land management and restoration of degraded lands and cultivated organic soils. Lower, but still significant mitigation potential is provided by water and rice management, set-aside, land use change and agroforestry, livestock management and manure management. The global technical mitigation potential from agriculture (excluding fossil fuel offsets from biomass) by 2030, considering all gases, is estimated to be approximately 5500-6000Mt CO2-eq.yr-1, with economic potentials of approximately 1500-1600, 2500-2700 and 4000-4300Mt CO2-eq.yr-1 at carbon prices of up to 20, up to 50 and up to 100 US$ t CO2-eq.-1, respectively. In addition, GHG emissions could be reduced by substitution of fossil fuels for energy production by agricultural feedstocks (e.g. crop residues, dung and dedicated energy crops). The economic mitigation potential of biomass energy from agriculture is estimated to be 640, 2240 and 16 000Mt CO2-eq.yr-1 at 0-20, 0-50 and 0-100 US$ t CO2-eq.-1, respectively.

Experimental economists are leaving the reservation. They are recruiting subjects in the field rather than in the classroom, using field goods rather than induced valuations, and using field context rather than abstract terminology in instructions. We argue that there is something methodologically fundamental behind this trend. Field experiments differ from laboratory experiments in many ways. Although it is tempting to view field experiments as simply less controlled variants of laboratory experiments, we argue that to do so would be to seriously mischaracterize them. What passes for “control” in laboratory experiments might in fact be precisely the opposite if it is artificial to the subject or context of the task. We propose six factors that can be used to determine the field context of an experiment: the nature of the subject pool, the nature of the information that the subjects bring to the task, the nature of the commodity, the nature of the task or trading rules applied, the nature of the stakes, and the environment that subjects operate in.

(R)-Trichostatin A (TSA) is a Streptomyces product which causes the induction of Friend cell differentiation and specific inhibition of the cell cycle of normal rat fibroblasts in the G1 and G2 phases at the very low concentrations. We found that TSA caused an accumulation of acetylated histone species in a variety of mammalian cell lines. Pulse-labeling experiments indicated that TSA markedly prolonged the in vivo half-life of the labile acetyl groups on histones in mouse mammary gland tumor cells, FM3A. The partially purified histone deacetylase from wild-type FM3A cells was effectively inhibited by TSA in a noncompetitive manner with Ki = 3.4 nM. A newly isolated mutant cell line of FM3A resistant to TSA did not show the accumulation of the acetylated histones in the presence of a higher concentration of TSA. The histone deacetylase preparation from the mutant showed decreased sensitivity to TSA (Ki = 31 nM, noncompetitive). These results clearly indicate that TSA is a potent and specific inhibitor of the histone deacetylase and that the in vivo effect of TSA on cell proliferation and differentiation can be attributed to the inhibition of the enzyme.

Almost fifty million people are food insecure in the United States, which makes food insecurity one of the nation's leading health and nutrition issues. We examine recent research evidence of the health consequences of food insecurity for children, nonsenior adults, and seniors in the United States. For context, we first provide an overview of how food insecurity is measured in the country, followed by a presentation of recent trends in the prevalence of food insecurity. Then we present a survey of selected recent research that examined the association between food insecurity and health outcomes. We show that the literature has consistently found food insecurity to be negatively associated with health. For example, after confounding risk factors were controlled for, studies found that food-insecure children are at least twice as likely to report being in fair or poor health and at least 1.4 times more likely to have asthma, compared to food-secure children; and food-insecure seniors have limitations in activities of daily living comparable to those of food-secure seniors fourteen years older. The Supplemental Nutrition Assistance Program (SNAP) substantially reduces the prevalence of food insecurity and thus is critical to reducing negative health outcomes.

This paper considers a statistical model for a production frontier that is consistent with the traditional (nonstochastic) definition of a production function given in microeconomic theory. Limiting cases of the model are the familiar average production function and an envelope production function. Maximum‐likelihood estimators for the parameters of the model are defined. The three related models are applied in the estimation of a production frontier for the Pastoral Zone of Eastern Australia with use of data from the Australian Grazing Industry Survey.

The 7 billion global population is projected to grow by 70 million per annum, increasing by 30 % to 9.2 billion by 2050. This increased population density is projected to increase demand for food production by 70 % notably due to changes in dietary habits in developing countries towards high quality food, e.g. greater consumption of meat and milk products and to the increasing use of grains for livestock feed. The availability of additional agricultural land is limited. Any expansion will happen mostly at the expense of forests and the natural habitats containing wildlife, wild relatives of crops and natural enemies of crop pests. Furthermore, more agricultural land will be used to produce bio-based commodities such as biofuel or fibre instead of food. Thus, we need to grow food on even less land, with less water, using less energy, fertiliser and pesticide than we use today. Given these limitations, sustainable production at elevated levels is urgently needed. The reduction of current yield losses caused by pests is a major challenge to agricultural production. This review presents (1) worldwide crop losses due to pests, (2) estimates of pesticide-related productivity, and costs and benefits of pesticide use, (3) approaches to reduce yield losses by chemical, as well as biological and recombinant methods of pest control and (4) the challenges of the crop-protection industry. The general public has a critical function in determining the future role of pesticides in agriculture. However, as long as there is a demand for pesticide-based solutions to pest control problems and food security concerns, the externality problems associated with the human and environmental health effects of pesticides need also to be addressed.

The research reported here examines the relationship between risk perceptions and willingness to address climate change. The data are a national sample of 1225 mail surveys that include measures of risk perceptions and knowledge tied to climate change, support for voluntary and government actions to address the problem, general environmental beliefs, and demographic variables. Risk perceptions matter in predicting behavioral intentions. Risk perceptions are not a surrogate for general environmental beliefs, but have their own power to account for behavioral intentions. There are four secondary conclusions. First, behavioral intentions regarding climate change are complex and intriguing. People are neither “nonbelievers” who will take no initiatives themselves and oppose all government efforts, nor are they “believers” who promise both to make personal efforts and to vote for every government proposal that promises to address climate change. Second, there are separate demographic sources for voluntary actions compared with voting intentions. Third, recognizing the causes of global warming is a powerful predictor of behavioral intentions independent from believing that climate change will happen and have bad consequences. Finally, the success of the risk perception variables to account for behavioral intentions should encourage greater attention to risk perceptions as independent variables. Risk perceptions and knowledge, however, share the stage with general environmental beliefs and demographic characteristics. Although related, risk perceptions, knowledge, and general environmental beliefs are somewhat independent predictors of behavioral intentions.

Asymmetric price transmission has been the subject of considerable attention in agricultural economics. It is not only important because it may point to gaps in economic theory, but also because its presence is often considered for policy purposes to be evidence of market failure. In this paper we survey the literature on asymmetric price transmission. A wide variety of often conflicting theories of, and empirical tests for, asymmetry co‐exist in this literature. We classify the different types and causes of asymmetric price transmission and describe the econometric techniques used to quantify it. We also briefly review the results of empirical applications. Outstanding methodological problems and suggestions for future research are discussed. Our main conclusion is that the existing literature is far from being unified or conclusive, and that it has often been largely method‐driven, with little attention devoted to theoretical underpinnings and the plausible interpretation of results. Hence, much interesting theoretical and empirical work remains to be done.

Transgenic maize engineered to express insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) has become widely adopted in U.S. agriculture. In 2009, Bt maize was planted on more than 22.2 million hectares, constituting 63% of the U.S. crop. Using statistical analysis of per capita growth rate estimates, we found that areawide suppression of the primary pest Ostrinia nubilalis (European corn borer) is associated with Bt maize use. Cumulative benefits over 14 years are an estimated $3.2 billion for maize growers in Illinois, Minnesota, and Wisconsin, with more than $2.4 billion of this total accruing to non-Bt maize growers. Comparable estimates for Iowa and Nebraska are $3.6 billion in total, with $1.9 billion for non-Bt maize growers. These results affirm theoretical predictions of pest population suppression and highlight economic incentives for growers to maintain non-Bt maize refugia for sustainable insect resistance management.

With current intensive agriculture practices and industrialization, pollution of natural resources like land and water with heavy metals, organic pollutants, radionuclides, pesticides, and fertilizers has become a major concern. Phytoremediation is a cost-effective and environmentally friendly technique that utilizes plants to immobilize, uptake, reduce toxicity, stabilize, or degrade the compounds that are released into the environment from different sources. Studies have shown that heavy metals, organic contaminants, radionuclides, antibiotics, and pesticides can be remediated using plants. Though phytoremediation has been practiced since decades, it is still an emerging technology. This review article summarizes existing information and synthesizes the recent findings on plant species suitable for use in phytoremediation through utilizing different mechanisms, aids that can enhance the efficiency of phytoremediation processes, and strengths and limitations that comes with the application of this technique. Diverse plants remediate different pollutants at different rates through one or multiple mechanisms. The limitations of phytoremediation can be overcome by using several aids including natural and chemical amendments, genetic engineering and natural microbial stimulation. Given the low-cost of phytoremediation compared to conventional technology and sustainability associated with plants and use of renewable energy, phytoremediation can be a reliable solution for a sustainable and economical remediation of soil and water from the organic and inorganic pollutants.

Abstract We compare consumer valuations of beef ribeye steaks from cattle produced without growth hormones or genetically modified corn in France, Germany, the United Kingdom, and the United States. Results suggest that French consumers place a higher value on beef from cattle that have not been administered added growth hormones than U.S. consumers; however, valuations of non‐hormone‐treated beef are statistically indistinguishable across Germany, the United Kingdom, and the United States. Results also suggest that European consumers place a much higher value on beef from cattle that have not been fed genetically modified corn than U.S. consumers.

A large body of literature suggests willingness‐to‐pay is overstated in hypothetical valuation questions as compared to when actual payment is required. Recently, “cheap talk” has been proposed to eliminate the potential bias in hypothetical valuation questions. Cheap talk refers to process of explaining hypothetical bias to individuals prior to asking a valuation question. This study explores the effect of cheap talk in a mass mail survey using a conventional value elicitation technique. Results indicate that cheap talk was effective at reducing willingness‐to‐pay for most survey participants; however, consistent with previous research, cheap talk did not reduce willingness‐to‐pay for knowledgeable consumers.

Understanding the capacity of agricultural systems to feed the world population under climate change requires projecting future food demand. This article reviews demand modeling approaches from 10 global economic models participating in the Agricultural Model Intercomparison and Improvement Project (AgMIP). We compare food demand projections in 2050 for various regions and agricultural products under harmonized scenarios of socioeconomic development, climate change, and bioenergy expansion. In the reference scenario (SSP2), food demand increases by 59-98% between 2005 and 2050, slightly higher than the most recent FAO projection of 54% from 2005/2007. The range of results is large, in particular for animal calories (between 61% and 144%), caused by differences in demand systems specifications, and in income and price elasticities. The results are more sensitive to socioeconomic assumptions than to climate change or bioenergy scenarios. When considering a world with higher population and lower economic growth (SSP3), consumption per capita drops on average by 9% for crops and 18% for livestock. The maximum effect of climate change on calorie availability is -6% at the global level, and the effect of biofuel production on calorie availability is even smaller.

Abstract Modified atmosphere packaging (MAP) extends shelf-life of most fishery products by inhibiting bacterial growth and oxidative reactions. The achievable extension of shelf-life depends on species, fat content, initial microbial population, gas mixture, the ratio of gas volume to product volume, and most importantly, storage temperature. The shelf-life of fishery products is usually limited by microbial activity, although for some fatty fishes or at superchilled storage, it can be limited by nonmicrobial activity. Packaging of fishery products under modified atmospheres (MA) increases shelf-life compared with those packaged under air, but confers little or no additional shelf-life increase compared with vacuum packaging. The specific spoilage organism (SSO) of MA packaged cod at 0 °C has been found to be Photobacterium phosphoreum. Whether or not this bacterium is the general SSO for all marine temperate fishes at different storage temperatures and under various CO2/N2/O2 mixtures needs to be resolved. Without proper control of storage temperature, the benefits of MAP may be lost. Higher temperatures inevitably lead to less dissolved CO2 in the product and consequently loss of inhibitory effect, which may result in higher microbial and enzymatic activity, and uncertainties concerning the microbial safety, as food-borne pathogens might be present in the product.

Four hypotheses concerning the character and consequences of participation in an ethnic enclave economy are examined. The first concerns the justifiability of operationalizing enclave participation on the basis of place of residence, as done in recently published research. The second and third pertain to the effects of ethnic economy participation on entrepreneurs and workers, respectively. The fourth deals with determinants of self-employment among ethnic minorities. Two data sets are employed in this analysis: the 1980 Census individual sample for Cuban-born adult immigrants in South Florida and a 1983-86 longitudinal survey of Mariel entrants in the same area. These two independent data sets permit a more authoritative evaluation of the hypotheses. They also allow an assessment of the extent to which earlier findings about the pre-1980 Cuban-born population apply to the more recent entrants. Results consistently contradict depictions of ethnic enterprise as vehicles for exploitation and of enclaves as mere residential agglomerations. These structures are defined by physical proximity of firms, not dwellings. Ascriptive factors-primarily gender and marital status-play a decisive role in the emergence of enclave enterprise net of human capital endowments. Theoretical implications of these findings, in particular the relationship between intact nuclear families and the rise of an entrepreneurial minority, are discussed.

Abstract In this article we estimate the technical and environmental efficiency of a panel of Dutch dairy farms. Nitrogen surplus, arising from the application of excessive amounts of manure and chemical fertilizer, is treated as an environmentally detrimental input. A stochastic translog production frontier is specified to estimate the output‐oriented technical efficiency. Environmental efficiency is estimated as the input‐oriented technical efficiency of a single input, the nitrogen surplus of each farm. The mean output‐oriented technical efficiency is rather high, 0.894, but the mean input‐oriented environmental efficiency is only 0.441. Intensive dairy farms are both technically and environmentally more efficient than extensive farms.

In many empirical studies of the effect of social programs researchers assume that, conditional on a set of observed covariates, assignment to the treatment is exogenous or unconfounded (aka selection on observables). Often this assumption is not realistic, and researchers are concerned about the robustness of their results to departures from it. One approach (e.g., Charles Manski, 1990) is to entirely drop the exogeneity assumption and investigate what can be learned about treatment effects without it. With unbounded outcomes, and in the absence of alternative identifying assumptions, there are no restrictions on the set of possible values for average treatment effects. This does not mean, however, that all evaluations are equally sensitive to departures from the exogeneity assumption. In this paper I explore an alternative approach, developed by Paul Rosenbaum and Donald Rubin (1983), where the assumption of exogeneity is explicitly relaxed by allowing for a limited amount of correlation between treatment and unobserved components of the outcomes. The starting point of the sensitivity analysis is the assumption that the exogeneity assumption is satisfied only conditional on an additional unobserved covariate. Making assumptions about the effect of the unobserved covariate on the outcome and its correlation with the treatment, I trace out the set of possible values for the treatment effect of interest. By considering a sufficiently large set of possible correlations with outcomes and treatment, one can recover the bounds on the treatment effect derived by Manski (1990). The approach here, in the spirit of Rosenbaum and Rubin (1983) and Rosenbaum (1995), is to allow only a limited amount of correlation and to judge the sensitivity of average treatment-effect estimates to such correlations. There are two novel features of the proposed analysis. First, rather than formulate the sensitivity in terms of coefficients on the unobserved covariate, the sensitivity results are presented in terms of partial R values, which may be easier to interpret. Second, the partial R values of the unobserved covariates are compared to those for the observed covariates in order to facilitate judgments regarding the plausibility of values necessary to substantially change results obtained under exogeneity. The proposed sensitivity analysis is conceptually related to the practice of assessing sensitivity of estimates by comparisons with results obtained by discarding one or more observed covariates (James Heckman and V. Joseph Hotz, 1989; Rajeev Dehejia and Sadek Wahba, 1999; Jeffrey Smith and Petra Todd, 2001). The attraction of the sensitivity analysis is that it is more directly relevant: one is not interested in what would have happened in the absence of covariates actually observed, but in biases that are the result from not observing all relevant covariates.

Abstract In the literature, a variety of approaches have been used to calculate demand elasticities in almost ideal demand system (AIDS) models of demand. It is common to estimate the linear approximate almost ideal demand system (LA/AIDS) instead of the AIDS. When the LA/AIDS is estimated, all of the previously reported approaches to compute elasticities are theoretically incorrect. This paper presents correct formulas for LA/AIDS elasticities and illustrates the potential errors from using incorrect computing formulas.

Institutions based on the concept "common property" have played socially beneficial roles in natural resources management from economic pre-history up to the present. "Property," as applied to natural resources, is a "primary" social institution both because of its own importance and because several important "secondary" institutions, including taxation, credit and tenancy, are derived from it. Common property, with the institutional regulation it implies, is capable of satisfactory performance in the management of natural resources, such as grazing and forest land, in a market economy. In reality, common property institutions are much in evidence in the evolution of institutions to remedy overfishing. Riparian institutions regulated the use of water from surface streams in England and on the continent long before formal riparian law was developed in Anglo-Saxon common law and German land law. The continued operations of commons both in England and on the continent answers the question raised earlier about the viability of common property in the market system.

Abstract Property rights reform is typically hypothesized to boost investment through investment demand and credit supply effects. Yet when the credit supply effect is muted, property rights reform would be expected to induce liquidity‐constrained farms to reduce investment in movable capital even as they increase investment in attached capital. This expectation is corroborated by econometric analysis of panel data from Paraguay. While all farmers experience a positive investment demand effect, liquidity‐constrained producers correspondingly reduce their demand for movable capital. Given an estimated pattern of wealth‐biased liquidity constraints, property rights reform will get institutions “right” for only wealthier producers.