Impact of copula choice on the modeling of crop yield basis risk

A number of problems in agricultural economics involve modeling joint distributions for which the assumption of multivariate normality may not be warranted. Yet, very little work has been conducted evaluating competing methods for modeling joint dependence. We develop a simulation framework to evaluate the bias and efficiency impacts of copula choice in the context of evaluating county‐to‐farm basis risk. The results suggest significant differences in performance across various copulas and approaches. The findings have important implications for risk analysis, insurance, and policy modeling problems in agriculture regarding the selection of method to model dependence among random variables.     

Estimating consumer willingness to pay for food quality with experimental auctions: the case of yellow versus fortified maize meal in Kenya

Biofortification of maize with provitamin A carotenoids is a new approach to the alleviation of vitamin A deficiencies in Africa. Unfortunately these varieties are yellow or orange, while consumers generally prefer white. Consumer willingness to pay for yellow and fortified maize was compared in experimental auctions in three regions in Kenya. The premium that consumers are willing pay for fortified maize (24%) was higher than the discount they require to buy yellow maize (11%), and in one zone consumers prefer yellow. Yellow color is, therefore, not an impossible obstacle for biofortified maize, although it would clearly be easier to introduce this maize first in regions where yellow maize is currently grown.     

Willingness to pay for brands: a cross‐region,cross‐category analysis

Using survey data collected in multiple locations (California and Texas in the United States and Revohot in Israel), we quantify category‐ and location‐specific variations of consumers’ willingness to pay (WTP) for brand products after controlling for consumer characteristics. We find that consumers have a similar qualitative assessment of brand value in different product categories across different locations. That is, consumers have a stronger preference and higher WTP for brands in consumer electronics, followed by clothing and then processed food, and the lowest in fresh produce. Furthermore, we simulate price premiums and market shares of brands relative to generic products in different categories. Simulation results suggest that brands in fresh produce have the highest price premium but lowest market share. Despite the similarities, the magnitude of WTP for brands as well as the simulated price premium and the corresponding market share in the same product category are location variant. The similarities and dissimilarities suggest validity of having global brand strategies adapted to local conditions, that is, the so‐called “thinking globally and acting locally” strategy.     

The impact of entry costs on export market participation in agriculture

Theoretical models of market entry imply that sunk costs are an important factor in the decision to export. Following Helpman, Melitz, and Rubinstein (2008) , we develop a simple model of foreign market participation and use a Bayesian method to estimate the resulting dynamic discrete‐choice model with lagged dependent variable. Employing a balanced panel data that follows 81 trading partners for 30 years from 1971 to 2000, we estimate our model and compute the marginal effect of sunk costs on the likelihood of export market participation. We find that such costs are economically and statistically important for trade in all of the six major agricultural commodities (Cereals, Dairy, Fish, Meat, Vegetables and Fruits, and Sugar), for agricultural producers in both developed and developing countries. We also find evidence suggesting that, in general, market access for both developed and developing exporters had improved in the years following the Uruguay round of trade negotiations (1995–2000).     

Informal barriers and agricultural trade: does monetary integration matter?

EU enlargement and the recent sovereign‐debt crisis of Euro zone countries have revived the debate around the (European Monetary Union) EMU. In this article we ask how informal barriers to agricultural and food trade have changed since the introduction of the common European currency, and whether this evolution can be attributed to monetary integration. We focus on the foreign trade of the 11 EMU founder countries over a nine‐year period covering the creation of the EMU and find a diminishing marginal trade impact of both information and institutional barriers. We find a lower level of trade barriers, but cannot attribute this outcome to the introduction to the Euro.     

Production risk,risk aversion and the determination of risk attitudes among Spanish rice producers

Agricultural production is subject to risk and the attitudes of producers toward risk will influence input choices insofar as these affect production risk. Risk attitudes in turn may be affected by certain socioeconomic characteristics of producers. Using 2004 survey data from a cross‐section of 130 Spanish rice farms, we estimate risk‐aversion coefficients of farmers and investigate the influence of a series of socioeconomic variables on their risk attitudes. Our results show that farmers exhibit risk‐averse behavior and that risk attitudes are related to a series of socioeconomic characteristics. In particular, the belief that the farm will continue after the producer retires is found to increase the degree of risk aversion, while age is found to have nonlinear effects on risk aversion. Off‐farm income, especially from nonagricultural activities, is found to reduce risk aversion. Neither the educational level of the producer nor the presence of dependents on the household is found to have an effect on risk preferences. Regarding the production technology, we find that land, labor, and fitosanitary products are risk‐reducing inputs, whereas capital, seeds, and fertilizer all increase risk.     

Shifting cultivation and forest pressure in Cameroon

Shifting cultivation is often blamed as a principal cause of deforestation in tropical Africa. It is claimed that the practice is unsustainable because shortened fallow lengths result in soils too degraded to support forest vegetation. The decline in fallow lengths is often attributed to increases in population density and greater market participation. The conventional wisdom makes several claims that are as yet unsubstantiated. This article investigates whether there is evidence to support two of these claims in southern Cameroon. First, using both cross‐sectional and panel data, I find that there is indeed a robust negative association between fallow lengths and population density in the study area and weaker evidence for a negative relationship between fallow lengths and market participation. Second, a stochastic frontier production function approach is used to investigate the marginal contribution of fallow to output. Results indicate that fallow lengths are not low enough to be affecting yields and therefore do not appear to be resulting in declines in soil fertility. Thus overall, while some of the assumptions of the conventional wisdom appear to be true, there is little evidence to support its dramatic conclusion that shifting cultivators are causing deforestation in the forested region of Cameroon.     

Convergence and divergence in regional agricultural productivity growth: evidence from Italian regions, 1951–2002

This article analyzes long‐term agricultural Total Factor Productivity (TFP) growth at regional level by testing its time‐series properties and identifying factors associated with divergence as opposed to convergence. The empirical application concerns Italian regions over the 1951–2002 time period. TFP growth decomposition ultimately attributes the observed productivity growth performance to these contrasting (convergence vs. divergence) forces. We find that technological spillovers are the key convergence force regardless of how the spillover effects are computed. At the same time, forces favoring convergence are almost offset by divergence forces (mainly scale or learning effects). This decomposition may explain the persistence of TFP growth rate differences in Italian agriculture, and could be applicable elsewhere.     

Off‐farm work,technical efficiency,and rice production risk in Taiwan

This article investigates the differences in yield production, production efficiency, and yield risk for farmers both with and without off‐farm work. Using a nationwide survey of rice farmers in Taiwan, we estimate two stochastic production frontier models that accommodate technical inefficiency and production risk simultaneously for farmers both with and without off‐farm work. The stochastic dominance criterion is then applied to compare the differences in the distributions of the estimated technical efficiency and yield risk between groups. The empirical results indicate that these two groups of farmers use resources in different ways, and off‐farm work is not necessarily associated with lower technical efficiency. For farmers in the lower percentiles of the efficiency distribution, those with off‐farm work are more efficient than their counterparts without off‐farm work. In addition, farmers with off‐farm work face higher production risk and this result is robust for the entire distribution.     

World market integration for export and food crops in developing countries: a case study for Mali and Nicaragua

Using a generalized error correction model, this article measures and compares market integration for export cash crops versus imported food crops for Mali and Nicaragua, and computes transmission elasticities between changes in the goods’ border and domestic prices. Both Mali and Nicaragua obtain the bulk of their export revenue from a particular agricultural commodity—cotton for Mali and coffee for Nicaragua—and both import the same key staple food of rice. To reap the economic gains from this trade specialization, the two countries’ agriculture must be well‐integrated into world markets. The two countries present an important policy contrast that affects their degree of world market integration and price transmission. In Mali, a parastatal enterprise controls its cotton industry, while Nicaragua has less state direction over agriculture. Reflecting this difference, the results show that for both its main export and import commodity, Nicaragua is more integrated into world markets and has higher price transmission than Mali. The results for Nicaragua also show much higher integration and price transmission for its main agricultural export (coffee) than its major import (rice).