房地产价格与通货膨胀、产出的关系——理论分析与基于中国数据的实证检验

本文运用一个简单的数理模型与四象限模型分析了房地产价格影响通货膨胀与产出的机制,结论是:房地产价格通过影响总需求对物价水平产生压力,其中,房价对储蓄的边际影响十分重要。在此基础上,综合运用相关性分析、协整检验、脉冲响应函数与方差分解等方法实证检验我国房地产价格与通货膨胀、产出的关系,其结论是:短期内,房地产价格对通货膨胀与产出的影响十分有限,长期则对通货膨胀与产出产生重要的影响,并且,在房价与通货膨胀、产出之间存在正反馈作用机制。这意味着在一个平稳的宏观经济环境中,这种正反馈机制可能会引发经济过热和房价泡沫。     

使用差价补偿策略的寡头竞争模型

差价补偿策略,是近年来在国内兴起的一种企业间竞争策略。从博弈论角度来看,对消费者承诺差价补偿,即是向竞争对手发出了一种不打价格战的可置信的威胁信号,可以有效地避免企业间的价格竞争;从市场营销角度来看,差价补偿策略会影响消费者行为,改变消费者预期,最终促使市场竞争向着企业有利的方向发展。本文对差价补偿策略建立了一个数学模型,分析企业采用差价补偿策略的原因以及竞争双方博弈的均衡结果。     

液体腰轮流量计示值误差测量结果的不确定度评定

结合中国石油长庆油田分公司原油流量计量的实际,利用测量不确定度评定的知识,通过建立数学模型、分析各输入量的标准不确定度、合成标准不确定度及扩展不确定度、给出测量不确定度报告,以达到对液体腰轮流量计示值误差测量结果的不确定度评定的目的。     

可再生能源发电并网后大电网运行的智能调度

随着风力发电等可再生能源的并网及需求响应的实施,电力系统平衡稳定运行的不确定因素显著增加为应对这些不确定性,区域输电组织（RTO）或大型电网公司的调度系统需要在传统的实时监控基础上有更强的超前预测能力提出了一种新型的调度体系——发电控制应用（GCA）,以应对可再生能源并网带来的挑战。此系统凭借动态的、鲁棒的调度算法和灵活的系统配置,使调度系统可以确保电力系统具有足够的跟踪能力以应对可再生能源的不确定性、间歇性,保证大电网运行的可靠性     

Sustaining Collusion Via a Fuzzy Trigger

Probability theory is the standard economic representation of uncertainty, although it is not always an accurate one. Fuzzy logic is an alternative representation that does not require individual beliefs regarding the explicit functional form of uncertainty. This paper applies fuzzy logic to an oligopoly trigger pricing game. The fuzzy trigger pricing game reverses the standard cyclical price war prediction; collusion-sustaining price wars are most likely to occur during times of high demand. The fuzzy model also predicts that markets with relatively volatile prices are more likely to undergo collusion-sustaining price wars. The predictions are consistent with available empirical evidence.     

Small farmer cooperatives and voluntary coffee certifications: Rewarding progressive farmers of engendering widespread change in Costa Rica?

Our research examines the benefits and drawbacks for cooperatives who participate in voluntary coffee certifications. We interviewed administrators at twenty Costa Rican coffee cooperatives about management practices related to voluntary certification. Voluntary certifications are popular among coffee cooperatives. Access to certified markets is facilitated by state support of the cooperative sector, regulation of the coffee sector and well-enforced environmental and social laws. However, there are no significant or consistent financial incentives for farmers to pursue certification. Multiple certifications may lower auditing and implementation costs, but cooperatives rarely receive the full premium for multiply-certified coffee. Low market demand for certified coffee, weak price incentives and high auditing and management costs encourage cooperatives to certify only a portion of their members. This strategy rewards compliant farmers rather than inducing widespread change to farming practices among the entire membership. Though financial incentives are weak, certifications offer non-financial benefits to both farmers and cooperatives, including better management and more resilient cooperatives.     

Are USDA reports still news to changing crop markets?

This study investigates whether major USDA reports still provide important news to changing crop markets. The news component of each report, or market “surprise,” is measured as a difference between the USDA estimate and its private expectation in corn, soybeans, and wheat markets. Changes in the relevance of USDA information are assessed by examining changes in the magnitude of market surprises and shifts in the futures price reaction to these surprises, which isolates the impact of each report. The stable size of market surprises over time suggests that competition from alternative data sources has not reduced the news component of USDA crop reports. Increasing price reaction to most reports, including those facing competition from alternative information sources, suggests that value of public information may be enhanced in uncertain markets affected by structural changes.     

Understanding heterogeneity in price changes and firm responses to a national unhealthy food tax in Mexico

To address the high prevalence of overweight and obesity in Mexico, an eight percent ad valorem excise tax on non-essential energy-dense foods came into effect on 1 January 2014. This paper estimates price changes after the tax implementation among the top four food categories and by leading vs. non-leading firms using purchase information from over 6000 urban households in the 2012–2015 Nielsen Mexico Consumer Panel. We create product-city-month specific prices that correct for potential biases associated with household and retailer characteristics. Using these corrected prices, we conduct before and after quasi-experimental analyses and find that price increases were larger than eight percent for cookies but were less than eight percent for ready-to-eat cereals, salty snacks, and pre-packaged sweet bread. For the latter food group, event-study analyses on the gradual price change over time suggest that price changes might be the result of an increasing price trend rather than the tax implementation. Firm-level analyses mostly show that price increases by the leading firms were larger than the overall increase at the food market level, helping explain variability in post-tax declines in food purchases as reported in other research. We also find that price changes are generally underestimated when we do not correct prices for biases associated with households and retailers. These results improve our understanding of the mechanisms behind heterogeneous changes in purchases after the tax implementation. Additionally, these results can assist policymakers when designing or improving taxes on non-essential energy-dense foods at a time when these policy options are high on the agenda in many places.     

A model of West African millet prices in rural markets

In this article we specify a model of millet prices in the three West African countries of Burkina Faso, Mali, and Niger. Using data obtained from USAID’s Famine Early Warning Systems Network (FEWS NET) we present a unique regional millet price forecasting model that takes advantage of the panel nature of our data and accounts for the distance of rural markets from capital cities. Another novel aspect of our analysis is our use of the Normalized Difference Vegetation Index (NDVI) to detect and control for variation in conditions for productivity. We find that including NDVI information significantly improves price forecasts.     

The response of U.S. natural gas futures and spot prices to storage change surprises: Fundamental information and the effect of escalating physical gas production

We study the behavior of U.S. natural gas futures and spot prices on and around the weekly announcements by the U.S. Energy Information Administration of the amount of natural gas in storage. We identify an inverse empirical relation between changes in futures prices and surprises in the change in natural gas in storage and that this relation is not driven by the absolute size of the surprise. The evidence also indicates prices react first in the futures market for natural gas with that information then flowing to the spot market. Post 2005, corresponding to a period of significant increases in the production of natural gas in the United States, the response of prices to storage surprises was larger in absolute value. No evidence is found of economically meaningful reactions to the surprise other than on the date the storage news is released. The results demonstrate the importance of fundamental information in the formation of natural gas prices.