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1.
Limiting fertilizer use is becoming an important policy objective world-wide. However, the debate on appropriate policy measures is far from settled and evidence on fertilizer demand elasticities is still insufficient. Past studies on fertilizer demand leave several methodological and empirical issues open. This paper aims to contribute to the debate on the methodology of estimating fertilizer demand using single-equation methods. Dynamic aspects are also considered using error-correction modelling methodology and cointegration techniques. The model is applied using data front Greece. Short-run and long-run price elasticities of fertilizer demand with respect to own price and to output prices show significant response to price changes and the adjustment coefficient of fertilizer use to the error-correction term was found to be fairly rapid. The main policy conclusion of the paper is that reducing agricultural support may be an alternative and, perhaps, more effective way of reducing fertilizer demand than increasing fertilizer prices.  相似文献   

2.
The use of corn as an ethanol feedstock has been stimulated by US biofuels policy. This has changed both the position and the slope of the corn demand curve and increased the pass-through from crude oil to corn prices. The principal constraints on ethanol consumption and production have been regulation (the biofuels mandate), capacity constraints in ethanol refining and the blend wall, which puts a ceiling on the ethanol content of gasoline. The incidence of these constraints has varied over time. We model these impacts within the competitive storage model using structural break regression analysis. Our analysis shows that the pass-through has varied over time in relation to the share of ethanol in total US corn use. Our analysis provides robust empirical evidence of an increase in the pass-through from crude oil to corn prices over the period from the start of the century to a high level over 2004–2008 when corn use in ethanol was growing very fast. This enhanced sensitivity was driven by competition for corn as an ethanol feedstock with stock demand exerting strong upward pressure on the corn price.  相似文献   

3.
This article addresses how China is being affected by and is responding to the world food crisis. So far, Chinese officials have responded to higher world prices by drawing down stocks and limiting exports of major grains. These policy instruments were not available for soybeans, so domestic prices of soy and other oilseeds have risen with international prices. Using a global CGE model, we show that the initial world price rise was largely due to higher world oil prices and demand for biofuels as opposed to other factors, especially in maize and soybeans. China's response to this shock has kept domestic grain prices low relative to world grain markets and to domestic soybean prices. As grain stocks are depleted, however, demand growth will push domestic prices back into alignment. Anticipating this pressure on consumers and accelerating supply response through public investment will facilitate adjustment.  相似文献   

4.
This article presents an econometric model of winegrape prices which recognizes the existence of demand and supply imbalances in the Australian market. A “markets in disequilibrium” framework is employed to motivate modeling price changes as responding to variations in excess demand/supply. The disequilibrium price equation provides estimates of regional and varietal price discounts/premiums and a measure of the speed of disequilibrium price adjustment. The equilibrium assumption is rejected for the market and substantial differences between equilibrium and disequilibrium estimates point to the inaccuracies of assuming market clearing. Disequilibrium estimates point to significant differences between warm and cool regions and changing speed of disequilibrium adjustment over time.  相似文献   

5.
The methodology of LaFrance and Hanemann for analysing the structure of incomplete demand systems is applied to models that are linear or logarithmic in quantities, prices and/or income. The structure of each model is presented when the implications of consumer choice theory are satisfied. The usefulness of the approach is illustrated. It is shown that considerable prior information is obtained from the theory of consumer choice when it is applied to this set of functional forms for demand equations.  相似文献   

6.
A debate has been raging for centuries regarding the effects of interannual storage on commodity prices. Most analysts consider storage to function as a price stabilizer, while others place it at the core of an explanation of intriguing features of commodity price series, such as skewed distributions. Most studies have been developed in the context of the theory of competitive storage where random shocks affect supply or demand. Recently, the endogenous chaotic behavior of markets has become another possible hypothesis regarding the origin of commodity price fluctuations. We develop a nonlinear cobweb model with intra‐ and interannual storage, risk averse agents, and adaptive expectations. Like the theory of competitive storage, this nonlinear cobweb model with storage can reproduce some of the stylized facts of agricultural commodity prices (autocorrelation of first rank, low kurtosis, and skewness). In addition, the effects of storage on price variation are mixed. In the presence of interannual storage, chaotic price series show less variation compared to a situation without interannual storage but we find that storage contributes to the endogenous volatility of prices by making chaotic dynamics more likely.  相似文献   

7.
In a competitive market with free information flows, spatial arbitrage will ensure that average prices at geographically separate markets will move in unison. The speed of adjustment is related to information flows between markets; if adjustment lags exist, there may be opportunities for arbitragers to gain. The transmission of price information is modelled using Johansen's procedure and the existence of long-run arbitrage opportunities is investigated. An innovation analysis is used to examine the varying responses to changes in prices at spatially separate markets.  相似文献   

8.
The theory of demand and supply implies a positive relationship, or “price transmission” between the prices of products at different stages of manufacturing. This relationship was investigated with quarterly prices of softwood stumpage in the US South, and national prices of forest products, from 1977 to 2002. All prices, net of inflation, were found to be nonstationary and there was no evidence of co-integration between prices. Vector autogressive models, augmented by Granger causality tests and multiplier analysis showed that there was a one-to-one permanent positive response of the southern sawtimber stumpage price to a permanent change in the national lumber price. There was also a one-third permanent positive response of the national paper price to a permanent change in the national pulp price. There was no relation between regional pulpwood prices and national pulp or paper prices. When price transmission was significant, the full adjustment took about 2 years.  相似文献   

9.
Potential effects of alleged monopsony pricing of farm food products by supermarkets on farm product prices, quantities, incomes and land values are assessed relative to competitive behaviour. A long‐run comparative static equilibrium model is used. For export‐competing and import‐competing products, the farm food input supply curve facing the supermarkets is close to perfectly elastic and this limits monopsony behaviour. At the margin, the opportunity to reallocate agricultural land between traded and nontraded farm products means a highly elastic supply function for nontraded food inputs facing supermarkets and very limited monopsony effects.  相似文献   

10.
Recent changes in economic conditions have introduced notable changes in household beef consumption patterns in Cameroon. While consumers are concerned about the short- and long-run effects of these factors on beef consumption habits, policy makers are more worried about the appropriate period necessary for households to make complete adjustments in consumption since this information is vital for planning production. Static and dynamic demand frameworks involving the Nerlovian partial adjustment (PA) model are used to capture the dynamic nature of beef consumption parameters. Maximum likelihood estimates of the PA model reveal that the conditioning variables explain 79% of the variation in beef consumption. Income, previous consumption, own-price and prices of fish and pork are jointly important in explaining beef consumption habits. Beef is a normal good with pork and fish as substitutes and chicken as a complement. Long-run price and income elasticities are greater than but not significantly different from their short-run values, suggesting that adjustment in consumption is fast with about 80% of the difference between actual and ‘desired’ consumption being completed in about 2 years. Projections show that demand for beef will reach 109620 t by the year 2000. giving an incremental total and per capita demand of 31 730 tons and 1.84 kg, respectively.  相似文献   

11.
Abstract

Modeling results, from a U.S. International Trade Commission investigation, that illuminate potato-related competitive conditions, particularly U.S. market impacts of potato imports, are presented. Estimation and simulation results of a monthJy vector autoregression model of the U.S. fresh and frozen trench fry markets suggest that the own-price elasticity of fresh table potato demand is more moderately elastic than previously thought; that U.S. fresh potato and trench fry markets only modestly interact, because the fresh table market residually and infrequently supplies raw product to processors; and that increased U.S. imports of fresh Canadian potatoes are likely a regional problem in Northeast U.S. markets, and do not appreciably influence potato-related prices or quantities nationally. Given the scarce potato-related literature, the model's estimated market parameters arc of interest.  相似文献   

12.
Although meat demand is one of the most studied issues in agricultural economics, our understanding of this phenomenon has been hampered by valid concerns about model specification uncertainty. This article revisits the need for more general theories of aggregate U.S. meat demand. Using a Bayesian averaging of classical estimates approach, we draw comprehensive inferences over 1,048,576 demand systems. We find very little evidence supporting the need for more general theories that include demand determinants beyond prices and expenditures. We find strong evidence in support of symmetry and negativity, but strong evidence against homogeneity, which is consistent with other research.  相似文献   

13.
This article analyzes consumer preference for fruit and vegetables when, by using time series with socioeconomic characteristics of households, there can be seemingly unobserved quality effects, which are increased by aggregation. The changes in Spanish demand for fresh and processed fruit and vegetables over the period 1987–2000 are discussed. Following previous tests and analyses, quantities are taken as predetermined and prices as matching the offer conditions. Thus, quality effects (based on the nutritional and/or health value of the product) are estimated from the error terms associated with the functions of the unit values. Quality variables are introduced as taste shifters in the inverse demand system (Laitinen–Theil model). The results show the positive effects of quality differences on the normalized price for the group of products through own‐quality flexibilities, and the negative effects between fresh and processed products through cross‐quality flexibilities.  相似文献   

14.
There are three important implications of this work. First, demand systems estimates that overlook supply response are as subject to simultaneous equations bias as single ad hoc demand equations. Theil shows theoretically that assuming supply curves are perfectly elastic, when in fact they are not will underestimate price responsiveness in demand equations. An empirical example is presented that demonstrates that the price elasticities generally increase when upward-sloping supplies are assumed.
Second, the iterative testing procedure presented may provide direction for model building when the true structure of the system is unknown. For example, the results of the Wu-Hausman test indicate that assuming chicken supply is perfectly elastic in a model of the Japanese livestock industry is justified. The results also indicate that the supplies of Wagyu beef, dairy beef, pork and fish are upward-sloping and therefore should be modeled as endogenous variables in the demand system.
Third, the results emphasize the sensitivity of projections of Japanese beef imports to the assumptions underlying the demand system. If perfectly elastic meat supplies are assumed for an analysis of reducing Japanese beef import liberalization, the results will likely underestimate the impacts on beef imports.
In summary, the supply curves for agricultural products tend to slope upward within the time periods used for traditional policy analysis and demand system estimation, which in turn implies that prices are determined endogenously within the system. Endogenous price determination is contrary to the assumptions that underlie the theoretical foundations and many empirical applications of demand systems. We present a methodology to test for and adjust demand systems for endogeneity. The importance of this adjustment is demonstrated by using an analysis of the liberalization of the Japanese beef market.  相似文献   

15.
A vector autoregressive model containing ocean grain freight rates, grain shipments, idled tonnage, new carrier deliveries and fuel prices is used to evaluate dynamic linkages in the ocean grain transport market. Dynamic relationships are of particular importance in ocean freighting months because freighting services are often contracted several months before shipment. In addition, such markets may be slow to adjust to shocks because of significant short-run fixities in shipping services. Ocean grain freight rates are found to be responsive to fuel prices and new ship deliveries, but are not affected by demand shocks. Ship idling rates are found to be sensitive to fuel prices, grain shipments and freight rates. Significant adjustment lags are revealed.  相似文献   

16.
Nonlinear adjustment toward long-run price equilibrium relationships in the sugar-ethanol-oil nexus in Brazil is examined. We develop generalized bivariate error correction models that allow for cointegration between sugar, ethanol, and oil prices, where dynamic adjustments are potentially nonlinear functions of the disequilibrium errors. A range of models are estimated using Bayesian Monte Carlo Markov Chain algorithms and compared using Bayesian model selection methods. The results suggest that the long-run drivers of Brazilian sugar prices are oil prices and that there are nonlinearities in the adjustment processes of sugar and ethanol prices to oil price but linear adjustment between ethanol and sugar prices.  相似文献   

17.
[目的]玉米在国家粮食安全中占有重要地位,是国内外市场联系最为紧密的大宗农产品之一。文章旨在探讨收购政策市场化改革前后,国内外玉米价格传导关系是否发生变化,为政府推进玉米供给侧改革提供理论依据。[方法]该文选取2009—2018年国内外玉米价格周度数据,利用向量误差修正模型和门限向量误差修正模型分别对收购政策市场化改革前后国内外玉米市场间价格传导关系进行实证分析。[结果]长期内,国内外玉米价格存在长期稳定的均衡关系,国际玉米价格对国内玉米价格具有持续稳定的正向传导关系;短期内,收购政策市场化改革前,国内外玉米价格间存在线性调整关系,具体表现为国际玉米价格向国内玉米价格单向传导关系;而收购政策市场化改革后,国内外玉米价格短期非均衡误差调整动态存在门限非对称调整关系,且改革后未来国内玉米价格受到当期国内玉米价格影响较大。[结论]这些结论对推进玉米供给侧改革,维护国内玉米市场的健康有序发展有一定的参考作用。  相似文献   

18.
Using a competitive dynamic optimization model, the difference between unused and used industrial milk quota values is shown to give an exact measure of the annual rental rate of production quota. Knowledge of the rental rate of production quota and output price can be used to impute the marginal cost of industrial milk production. However, if there is a transfer tax on production quota sales, the imputation of the equilibrium rental value of quota depends on the elasticity of demand and supply for quota as well as the level of the transfer assessment. The marginal cost of Ontario milk production is estimated for each year from 1980–81 to 1994–95, based on unused and used quota values. However, the imputed marginal cost estimates are not totally satisfactory. The results suggest that caution should be exercised in using the difference between unused and used quota prices as a measure of the rental rate of industrial milk production quota.  相似文献   

19.
INSURANCE MILK     
Where the production of milk for sale on the fresh milk market at 'controlled' prices is subject to nontransferable quotas the holders of quota who wish to maximise profits have a motive to maintain production above the quota level to insure against variations in demand for over-quota sales and yield. The concept of 'production of milk as insurance' is used to clarify the way in which such behaviour gives rise to social costs which could be avoided in a competitive market, by a permissive attitude to arbitrage, or where quotas can be traded.  相似文献   

20.
This paper derives long and short‐term economies of scope from a dual profit maximising model of production, using the concept of shadow prices. The dual model includes lagged netput quantities to reflect past experience in the production of outputs and the application of inputs. The framework is applied to aggregate data of specialised producers of vegetables in the Netherlands in the period 1981–1994. Adjustments of most netputs are instantaneous, with small adjustment lags being found for cucumbers, materials and services. Long and short‐term economies of scope indicate that at the sector level, there is an incentive towards specialisation in the production of tomatoes and a strong incentive towards diversification in case of all other outputs. Keywords: Generalised Maximum Entropy estimation, Economies of Scope, Horticulture.  相似文献   

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