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121.
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.  相似文献   
122.
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.  相似文献   
123.
Shifting cultivation and forest pressure in Cameroon   总被引:1,自引:0,他引:1  
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.  相似文献   
124.
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.  相似文献   
125.
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.  相似文献   
126.
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).  相似文献   
127.
Estimating the cost of liquidity in agricultural futures markets is challenging because bid‐ask spreads are usually not observed. Based on an ability to reflect simulated data from Roll's spread model, we assess the effectiveness of conventional and Bayesian bid‐ask spread estimators under different market conditions. Conventional serial covariance and absolute price change spread estimators appear to be biased. Hasbrouck's Bayesian estimator generates small costs of liquidity whose values depend on the correlation and noise in the data. The absolute value Bayesian estimator is precise and works well under conditions of high levels of noise and correlation usually found in agricultural futures markets. Using data from live cattle (LC) and lean hog (LH) contracts, we find similar patterns of performance that produce economically meaningful cost of liquidity differences.  相似文献   
128.
Dutch disease occurs when currency strengthening associated with a booming sector of an economy crowds out a lagging trade‐dependent sector. In this study, a Keynesian‐style model is specified to deduce hypotheses about how increased foreign direct investment (FDI) aimed at Mongolia's mining sector affects its agricultural sector. A key finding is that while econometric results suggest the increased FDI strengthened Mongolia's currency, its adverse effect on Mongolia's trade‐sensitive agricultural sector is not sufficiently strong to cause the sector to decline. Although Dutch disease was not detected, the posited mechanism clearly is important. Specifically, when currency strengthening is ignored the reduced‐form elasticity of agricultural value‐added with respect to FDI is 2.7 times larger than when currency strengthening is taken into account (0.103 vs. 0.038). Also, FDI‐induced currency strengthening causes the Keynesian multiplier to drop from 2.40 to 2.00 and the FDI multiplier to drop from 3.05 to 1.89.  相似文献   
129.
Organic agriculture, which produces commodities that can be qualitatively differentiated from conventional food products, has grown into an important market in many countries. The dynamics of commodity prices in both sectors are partly interdependent, but are also shaped by independent determinants and have rarely been studied. We analyze organic food markets and their interdependencies with conventional markets in the context of wheat markets in Germany, which have been subject to a number of fundamental changes during the last two decades. Based on institutional market characteristics, we suggest a flexible Markov‐switching asymmetric time series model. We find a pronounced temporal sequence of market phases that differ in their asymmetric dynamics and the extent to which the organic price is influenced by the conventional price. Organic wheat prices tend to be increasingly connected to prices of conventional wheat.  相似文献   
130.
We investigate the performance of the ordinary least squares (OLS)‐, M‐, MM‐, and the Theil–Sen (TS)‐estimator for crop yield data analysis in crop insurance applications using Monte Carlo simulations. More specifically, the performance is assessed with respect to trend estimation, prediction of future yield levels, and the estimation of expected indemnity payments. In agreement with earlier findings, other estimators are found to be superior to OLS in simple regression problems if yield distributions are outlier contaminated and heteroscedastic. While this conclusion is also valid for subsequent applications such as yield prediction and the estimation of expected indemnity payments, the difference between the considered estimators becomes less distinct. For these applications, we find particularly the M‐estimator to be a good compromise between high‐breakdown (very robust) estimators and the very efficient OLS‐estimator. Because no regression technique dominates all others in all applications and scenarios for error term distributions, our results underline that the choice of the estimation technique should be dependent on the purpose of the crop yield data analysis. However, alternative estimators such as M‐, MM‐, and TS‐estimator can reduce (and bound) the risk of unreliable or inefficient crop yield data analysis in crop insurance applications.  相似文献   
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