产需双重不确定情形下绿色农产品供应链的协调研究

为解决产需不确定性给绿色农产品供应链运营带来的复杂影响,寻求绿色农产品生产商和销售商面对产需双重不确定情形下各自的最优决策,研究从农产品产出和市场需求双重不确定性视角出发,结合目前消费者对绿色农产品的需求偏好,构建由生产商和销售商组成的Stackelberg博弈模型,探究收益共享契约能否有效协调产需都不确定的绿色农产品供应链。研究结果表明:分散决策时的批发价契约无法协调此供应链。引入收益共享契约后,在合适的共享系数范围内,生产商的农资投入量会增加,农产品的绿色度会比分散决策时高,同时销售商的销售价格降低;当农产品订购量变大后,引入契约后的生产商和销售商各自的利润相较于分散决策时更高。     

SELLING A LEMON UNDER DEMAND UNCERTAINTY

We consider a seller who has private information about the quality of her good but is uncertain about buyer arrivals. Assuming that the high‐quality seller insists on a price, we show that the low‐quality seller's surplus and pricing strategy crucially depend on buyers' knowledge about the demand state. If they are also uncertain about demand, then demand uncertainty increases the low‐quality seller's expected payoff, and her optimal strategy is to lower the price after some time. If buyers know the demand state, then demand uncertainty does not affect the low‐quality seller's payoff, but she must employ a sophisticated pricing strategy.     

RISKY PRODUCTION WITH EX-ANTE PRICES UNDER MONOPOLY ANALYTICAL AND SIMULATION RESULTS

This paper concerns the case of a monopolist facing multiplicative uncertainty in demand. Karlin and Carr (1962), henceforth KC, show that, when price and production are both chosen ex ante , the uncertainty price exceeds the certainty price. They also give a sufficient condition under which the firm locates above the certainty demand curve, but they do not consider the effect on the output level. In this note we replicate the KC results and then go further. In the special case that the price elasticity of certainty demand is constant, and the probability distribution for the uncertainty parameter in the demand function is uniform, output is unambiguously lower under uncertainty, and KC's condition for the firm to locate above the certainty demand curve can be strengthened to one that is both necessary and sufficient. The robustness of these results is tested under less stringent assumptions on demand, abandoning symmetry for a lognormal distribution of the uncertainty parameter. Simulation confirms that the results hold up, and also determines the effects upon the firm's decisions of an increase in demand uncertainty.     

Semicollusion vs. Full Collusion: The Role of Demand Uncertainty and Product Substitutability

We examine the profitability of two different cartel organizational forms: full collusion, under which firms collude on both price and quality, and semicollusion, under which firms collude on price only. We show that, in the presence of demand uncertainty that cannot be contracted upon in the cartel agreement, firms may be better off limiting their collusive agreement to price only. However, a positive relationship between demand uncertainty and the relative profitability of semicollusion exists only for low levels of demand substitutability. The converse is true for high levels of demand substitutability. Therefore, if demand substitutability is sufficiently high, no level of demand uncertainty will make semicollusion the optimal organizational form. In contrast, semicollusion is guaranteed to be optimal for a sufficiently low level of demand substitutability. The market structure described is motivated by and closely parallels that of shipping cartels. Received September 29, 2000; revised version received December 10, 2001 Published online: November 11, 2002     

A test of monopoly price dispersion under demand uncertainty

A test of the predictions of Dana’s (2001) model of monopoly price dispersion under demand uncertainty using ticket price data from Major League Baseball shows that ticket price dispersion changes systematically with demand uncertainty, verifying the predictions of the model.     

Separating the Roles of Speculators and Consumers: a Model of Futures Trade

The general equilibrium model of Britto (1984) is criticised. In particular, it is shown that allowing consumers to trade on the futures market leads to more complicated results than necessary. If consumers do not trade futures, and only producers and speculators do, results are greatly simplified. Consumer risk parameters, and parameters of producers production function are irrelevant. The differential between the futures price and the expected spot price, and the direction of futures trade is shown to depend in a straightforward way on the price elasticity of demand for the product on the spot market.     

PRICE DISPERSION AND DEMAND UNCERTAINTY: EVIDENCE FROM U.S. SCANNER DATA

I use the Prescott (1975) hotels model to explain variations in price dispersion across items sold by supermarkets in Chicago. The effect of uncertainty about aggregate demand on price dispersion is highly significant and quantitatively important: My estimates suggest that more than 40% of the cross‐sectional standard deviation of log prices is due to demand uncertainty. I also find that price dispersion measures are negatively correlated with the average price but are not negatively correlated with the revenues from selling the good (across stores and weeks) and with the number of stores that sell the good.     

Responses of Economic Activity to Global Oil Market Shocks: A Comparative Analysis of Major Net Oil‐Producing and ‐Consuming Countries

We argue that four channels drive oil price shocks during 1986M5–2013M1, namely the oil supply, aggregate demand, oil‐specific demand and real exchange rates. Our findings are that oil price shocks driven by oil supply positively affect net oil‐consumer countries faster than net oil‐producer countries. Oil price shocks driven by aggregate demand are largely country‐specific. Oil shocks driven by other demands influence net oil‐producers faster than net oil‐consumers negatively, and persistently mostly among net oil‐producers. Other shocks have large negative effects on the industrial production of all countries, with responses appearing very quickly and persisting for at least a year.     

Firms’ investment decisions in response to demand and price uncertainty

We investigate the effect of demand and price uncertainty on firms’ planned and realized investment from a panel of manufacturing firms. Uncertainty measures are derived from firms’ own expectations about demand and prices and firm's sales. We find that demand uncertainty at the time of planning depresses planned and subsequent realized investment. Firms do not revise their plans due to demand uncertainty at the time of spending, suggesting that reducing demand uncertainty will only have lagged effects on investment. We do not find any effect of price uncertainty. Our results are consistent with the behaviour of monopolistic firms with irreversible capital.     

Demand and cost impacts of the 2 mm technology program in the US motor-vehicle market

We assess the impact on demand and producers’ costs of a new technology implemented in the US auto industry, the 2 mm program. This is a fascinating case partially because of the unique collaboration among public agencies and a consortium of manufacturers and universities. Using a type of hedonic price model for demand, we show that the new technology was responsible for a short-lived increase in demand for vehicles produced by US automakers at increased producers’ costs. Firms that refused to participate in the consortium attained smaller net gains implementing the technology independently. Overall, our approach differs from that of previous analysts in that we (1) separate demand from supply, (2) employ a comprehensive vehicle database, spanning 1981–1998 data, including data on virtually all vehicle models sold in the USA, as well as data on plants’ and producers’ technology characteristics, and (3) rely on sales and production data rather than plant data. Also, we quantify the cost of not participating in the consortium.     

The effects of price on household demand for food and calories in poor countries: are our databases giving reliable estimates?

Food price policy relies heavily on estimated price elasticities of food demand to help balance the nutritional and economic objectives in poor countries. Economists use either unit values (ratios of household expenditure to quantity purchased) or community prices (enumerated from vendors in local markets) as proxies for market prices when estimating price elasticities with household survey data. Biases are believed to result from using unit values, due to measurement error and quality effects, but evidence on this issue is lacking and even less is known about community prices. This article provides an empirical evidence from Vietnam, which suggests that economists should exercise caution when estimating price elasticities from household surveys. A 14-food demand system is estimated alternatively with unit values or community prices, and the elasticity of calories with respect to rice prices is calculated. This elasticity is more than twice as large (?0.54 versus ?0.22) when community prices are used rather than unit values. Hence, conclusions about the nutritional effects of rice price increases appear sensitive to data choices made by economists. More generally, this discrepancy suggests that the household survey databases commonly used by economists may not provide reliable estimates.     

需求不确定性下供应商回收未售商品对季节性商品采购的影响

分析需求不确定性条件下,供应商回收零售商未售商品策略对零售商季节性商品采购量的影响,通过数学模型分别对不同需求状态和不同回收价情况下零售商最优采购量进行仿真,说明随着需求不确定性程度的增加,零售商商品的采购数量增加而期望利润下降;供应商通过优化批发价和回收价组合可以增加零售商在相同需求状态时的采购量,提高供应商的期望利润。     

Hypothetical Bias Reconsidered: Payment and Provision Uncertainties in a Threshold Provision Mechanism

We extend research on the consequentiality of stated preference choices to a threshold provision mechanism for public goods. We develop a simple theoretical model of option price to analyze how option price varies with payment and provision uncertainty. We explore whether threshold provision contributions are similarly influenced by payment and provision uncertainty using an induced value contribution experiment. Results suggest that: (1) the probability of payment has a negative effect on contributions; (2) the probability of provision has a positive effect on contributions. We offer subjective beliefs regarding payment and provision as a plausible systematic explanation for hypothetical bias.     

Price or quantity setting under uncertain demand and capacity constraints: An examination of the profits

This article considers price formation and quantity setting of a capacity-constrained risk-neutral firm facing uncertain demand. It is shown that the optimal price of a price-setting risk-neutral monopolist decreases with demand uncertainty. With a strictly convex demand function expected profits increase with uncertainty for a quantity-setting monopolist whereas expected profits decrease for a price-setting monopolist. Furthermore, similar results on the effect of uncertainty are derived for a differentiated goods industry.     

Structural oil price shocks and policy uncertainty

Increases in the real price of oil not explained by changes in global oil production or by global real demand for commodities are associated with significant increases in economic policy uncertainty and its four components (the volume of newspaper coverage of policy uncertainty, CPI forecast interquartile range, tax legislation expiration, and federal expenditures forecast interquartile range). Oil-market specific demand shocks account for 31% of conditional variation in economic policy uncertainty and 22.9% of conditional variation in CPI forecast interquartile range after 24 months. Positive oil shocks due to global real aggregate demand for commodities significantly reduce economic policy uncertainty. Structural oil price shocks appear to have long-term consequences for economic policy uncertainty, and to the extent that the latter has impact on real activity the policy connection provides an additional channel by which oil price shocks have influence on the economy. As a robustness check, structural oil price shocks are significantly associated with economic policy uncertainty in Europe and energy-exporting Canada.     

Adjustment costs and threshold effects in factor demand relationships

It has been recently argued that producers may not respond to every input price change in the way that a linear factor demand model would predict. This lumpy response is due to adjustment costs that are inherent in the act of adjusting the mix of inputs applied in the underlying production technologies. This study aims to provide a solid conceptual framework for these nonlinearities in factor demand relationships. Industry-specific implications of convex and non-convex adjustment costs for the linearity of the factor demand relationships as well as price and substitution elasticities are explored. A two-regime threshold system of factor demand equations is estimated for several manufacturing industries in the United States. Empirical results suggest significant threshold effects in the factor demand relationships in most nondurable goods sectors. The size and the nature of thresholds depend upon industry characteristics, including input composition and (non)convexity of underlying adjustment costs. Complete matrices of price and substitution elasticities for each industry are derived using estimates of threshold factor demand systems. Discussion of two contrasting cases in greater detail sheds light on how the effect of price shocks on factor demand relationships varies across industries with different adjustment cost structures.     

质量投资模型下的安全食品生产实体决策行为分析

食品生产实体的质量投资决策行为将影响食品市场的质量安全总体水平。本文依据经济学理论,构建了食品生产实体质量投资模型,并进行了案例分析。结果显示：影响食品生产实体做出质量投资决策的因素依次为安全食品价格、企业资本实力、质量投资量、政府支持。     

Prices Versus Quantities: Technology Choice,Uncertainty and Welfare

Technological improvements have proven essential in mitigating environmental problems such as climate change, depletion of the ozone layer and acid rain. While it is well-known that price- and quantity-based regulatory instruments provide different investment levels, the effects on the choice between different technologies have received scant attention. This paper expands on the prices versus quantities literature by investigating firms’ technology choice in the face of demand and supply side uncertainty. I show that the regulator can not design tradable emissions permits and an emissions tax such that the two regimes are equivalent, even in terms of expected values. Moreover, a tax encourages the most flexible abatement technology if and only if stochastic costs and the equilibrium permit price have sufficiently strong positive covariance, compared with the variance in consumer demand for the good produced. Finally, the firms’ technology choices are socially optimal under tradable emissions permits, but not under an emissions tax.     

Analysing Firm‐level Price Effects for Differentiated Products: The Case of Australian Wine Producers

The paper discusses and illustrates estimation methods for identifying and modelling the influence of producers on the prices for a differentiated product. A two‐step fixed effects approach is contrasted to the random effects specification. The techniques are employed to analyse prices for over 260 Australian premium wine producers. The fixed effects specification is preferred given significant correlation between wine attributes and random producer effects. The estimation of fixed producer price effects identifies statistically significant price premiums and discounts, which average 15%. Fixed producer price effects are estimated to depend on the quality reputation of the producer, its level of experience, producer size and the use of multibrands by conglomerates. In part, results indicate that price discounts are associated with producers who have low‐quality reputations, are small and recently established.     

The market power of OPEC 1973–2001

We apply a multi-equation dynamic econometric model on monthly data to test if the behaviour of OPEC as a whole or different sub-groups of the cartel is consistent with the characteristics of dominant producers on the world crude oil market in the period 1973–2001. Our results indicate that the producers outside OPEC can be described as competitive producers, taking the oil price as given and maximizing profits. The OPEC members do not fit the behaviour of price-taking producers. Our findings of low residual demand price elasticities for OPEC underpin the potential market power of the producer group, and are in line with the results in some recent energy studies. On the other hand, our findings indicate that neither OPEC nor different sub-groups of the cartel can be characterized as a dominant producer in the period 1973–1994. However, we find that the characteristics of a dominant producer to some extent fit OPEC-Core as from 1994. Thus, although OPEC clearly has affected the market price, the producer group has not behaved as a pure profit-maximizing dominant producer.