How did the price and income elasticities of natural gas demand in China evolve from 1999 to 2015? The role of natural gas price reform

As a cleaner,high-efficiency,and low-carbon fuel,natural gas has been an important fuel resource for China.To achieve a substantial increase in natural gas demand,China has sought to reform its natural gas pricing mechanism.Employing a set of unbalanced panel data for China’s 30 provinces covering 1999-2015,this study aims to estimate the evolving price and income elasticities of natural gas demand and explore the effect of natural gas price reform in China.For this purpose,a series of econometric techniques allowing for cross-sectional dependence and slope homogeneity is utilized.The results suggest that although natural gas demand in China still lacks negative price elasticity,the phenomenon is improving.Moreover,the estimates suggest that natural gas demand in China is indeed becoming increasingly sensitive to income changes.Our estimates also provide strong evidence in favor of the effect of natural gas price reform on the change in price elasticity as the price elasticity decreases in five of the seven regions.In addition,the results indicate large variations in the change in price and income elasticities of natural gas demand across China’s regions.Natural gas demand is becoming more price inelastic in Southwest China and Northwest China,while such demand in North China and East China responds less sensitively to income changes.These findings offer several policy suggestions for the reform of China’s natural gas market at the national and regional levels.

The Impact of Price on Chemical Fertilizer Demand in China

Since 1998,the national policies on chemical fertilizer in China have been concentrated in limiting price plus subsidizing,abolishing agricultural tax,giving direct subsidies to farmers,and other aspects.In order to analyze the impact of national policies on the consumption of chemical fertilizer,this article selects the consumption of chemical fertilizer per unit,chemical fertilizer price index and farmers'net income in different provinces during the period 1998-2007 as variables,to conduct regression analysis of chemical fertilizer expenditure function,and calculate the price elasticity and income elasticity of chemical fertilizer demand in different provinces over the decade based on the regression results.The results show that at present the basic consumption of chemical fertilizer for agricultural development in China is 0.35 t/hm 2 ,and the consumption of chemical fertilizer is excessive in some provinces;the chemical fertilizer market has not been really established,and the price has little impact on demand.This indicates that the chemical fertilizer is essential for agricultural economic development,and it increases along with the increase of farmers'income; the intervention of the national policy in chemical fertilizer price is a fundamental reason for the rising demand for chemical fertilizer.This also to some extent indicates that the policy effect of merely using environmental taxes to change farmers'consumption of chemical fertilizer is limited;there is a need to transform the existing policies purely promoting agricultural economic development,toward giving different subsidies in accordance with whether the farmers'fertilization pattern is beneficial to the environment.

Price Discrimination of Film Products and Building of Hierarchical Market under the Background of “Internet Plus”

Price Discrimination of film products is theoretically feasible and logically inevitable, and it has been used for a long time in film industry as well. However, there are practical paradoxes in the new environment due to market factors like popularization of Internet environment and Online to Offline(O2O) retailers between hierarchical markets. Compared with high-level markets, low-level markets are lack of conditions for differentiated lower price like cinema infrastructure, and environment for film consumption market, so that the consumption potential for market has not been motivated yet. Therefore, it is quite important to pay close attention to how to expand the market by clearer gradient pricing structures and Internet platform.

Mathematical model of the adjustment of the optimal price of the substituting commodity

In this paper, from the two economic concepts of the price elasticity of demand and the cross elasticity of demand, under the assumption that the operator＇s management goal is to obtain the profit maximization, the author established the mathematical model of the adjustment of the optimal price of the substituting commodity.

Impact of Urban Water Pricing on Future Water Demand： A ＇Socioeconomic＇ Study in Greece

The main aim of this study is to assess various aspects of the current water policy, investigate the perspectives of water saving, evaluate water price elasticity and explore new approaches toward sustainable water management in the water sector, through a questionnaire survey that has been performed in the city of Volos, Greece, concerning the residential sector. The appropriate design of water management measures presupposes the investigation of the influence of some selected variables to consumers＇ behavior. The price of water, the size of the dwelling, the indoor and outdoor uses, the educational level, the income of consumers as well as rainfall and temperature levels are examined, the residential water demand curve is estimated and projections of future water demand under different pricing policies are performed.

The Impact of Water Pricing Policy on Local Environment-An Analysis of Three Irrigation Districts in China

As a high priority in dealing with the problem of water scarcity, the effect of water pricing policy remains a controversial issue, especially the environmental effect. Using household-level panel data of three irrigation districts （IDs） in the northern China, this paper probes the potential impact of water price rising on local environment. The examination shows that farmers will reduce the rice area as a response to the rising surface water prices. The changing cropping pattern will exert three-fold environmental impacts, including the dropping groundwater level resulting from the reduction of seepage and percolation of irrigated water and overexploitation of groundwater, the negative effect of non-point pollution from fertilizer and pesticide application, and the loss of field irrigation facilities. Water pricing is not a valid means of significantly reducing agricultural water consumption due to the substitution of groundwater for surface water, it will lead to negative environmental effect. It is an imperative task for Chinese government to improve the management efficiency at IDs.

Study on Demand Response of Residential Power Customer

In order to optimize the ladder-pricing scheme in Shanghai, we present a multi-objective optimization model (MOOM). To build this model, first we use price elasticity theory;divide the ladder pricing into peak electricity bill and valley electricity bill in the time dimension to model the single-user demand response. Second based on the single-user demand response model, combined with the overall users’ electricity distribution density function, we build an all-users demand response model. The proposed model has two objectives: minimize energy consumption and maximize residents’ satisfaction. Simulation results confirm that the proposed model can optimize the ladder-pricing scheme.

The Application of the Theory of the Price Elasticity of Demand to the EMS Management

Express Mail Service (EMS) is the most competitive one of the post services. Price competition is the core of market competition and so for EMS. In this paper, we calculate the coefficient of demand elasticity and then put forward the price strategy for EMS to increase its competitive power.

Pricing Power of China's Cocoon and Silk Products in International Market:An Empirical Analysis Based on International Market Power

Do China＇s silk products only have advantage in number but no pricing power in international market？ In this paper, we used the residual demand elasticity model to estimate the international market power of China＇s silk products. The empirical results revealed that China＇s raw material products such as natural silk products and semi-finished products such as satin products had certain market power in the main export markets, but the finished silk products such as woman＇s blouse or shirts and shawls had no market power in the target markets including USA and Germany. The scale economy from resource endowment and great market share are the base of the international market power of natural silk products. The advantage from industry agglomeration and great market share are the source of the international market power of satin products. Technical bottlenecks and inefficiency in brand building are the cause of unobvious international market power of China＇s finished silk products, and the competition from Italy and France has increased the difficulty to enhance market power. In order to consolidate and improve the international market power of China＇s silk products, it is suggested to stabilize the production scale and strengthen industrial base, to speed up the resources integration and optimize the industrial distribution, to strengthen science and technology innovation and adjust product structure, to speed up the brand construction and enhance the influence of brand, and to enlarge the scale of organization and achieve scale economies.

Methodology for Obtaining Electricity-Price Patterns in Customer Response Programs

The main objective of electricity regulators when establishing electricity markets is to decrease the cost of electricity through competition. However, this scenario cannot be achieved without a full participation of the electricity demand by reacting against electricity prices. The aim of this research is to develop tools for helping customers and aggregators to join price and demand response programs, while helping them to hedge against the risk of short-term price volatility. In this way, the capacity of and hybrid methodology （Self-Organizing Maps and Statistical Ward＇s Linkage） to classify high electricity market prices is analysed. Besides, with the help of Non-Parametric Estimation, some price-patterns were found in the abovementioned clusters. The contained knowledge within these patterns supplies customer market-based information on which to base its energy use decisions. The interest for this participation of customers in markets is growing in developed countries to obtain a higher elasticity in demand. Results show the capability of this approach to improve data management and select coherent policies to accomplish cleared demand offers amongst different price scenarios in a more flexible way.

刘易斯转折点、缴费负担转嫁与高龄农民工参加城镇职工基本养老保险趋势——理论推断与实际证据

高龄农民工特指户籍仍在农村、在本地从事非农产业或外出从业6个月及以上的50岁及以上劳动者。中国刘易斯转折点大概出现在2010—2014年。与人口结构尤其是年龄结构相对应的刘易斯转折点前后,高龄农民工参加城镇职工基本养老保险个人缴费负担和用人单位缴费负担转嫁内在地决定着高龄农民工参加城镇职工基本养老保险的比例及其变化趋势。刘易斯转折点之前高龄农民工参加城镇职工基本养老保险的比例偏低,刘易斯转折点之后高龄农民工参加城镇职工基本养老保险的比例会增加,实证检验证实了这一理论推断。为了提高高龄农民工未来的养老保障程度,提出以帕累托改进原则推进高龄农民工养老保障制度改革,督促高龄农民工与用人单位签订劳动合同,做好高龄农民工基本养老保险关系转移接续,实施多样化的高龄农民工养老保障方式。

考虑交叉价格弹性的城市天然气分时定价研究

近年来,全国各地天然气“气荒”现象突出,为缓解天然气使用压力,除了稳定的天然气进口外,有效的定价方式是其中关键。随着天然气需求区域及消费人群的增多,城市管网平稳运行压力增大,要求为天然气寻求能够实现缩小峰谷负荷差、维护市场稳定的定价方式。论文建立了对工业用户基于自弹性和交叉价格弹性的需求响应模型,考虑天然气价格自弹性以及不同时段间的交叉弹性的双重影响,并以此为基础,构建了分时定价仿真模型,对北京的城市天然气终端消费状况进行仿真模拟和分析。结果表明,1)分时定价实施效果峰同时段价格上调比例(峰谷价格差)之间成正相关,同居民用户天然气消费量占总用气量的比重呈负相关,居民消费占比越大,实施效果越差。2)天然气价格自弹性与交叉价格弹性对于分时定价政策效果有明显的重要作用。在不考虑政府对于燃气公司或者工业用户给予补贴等情况下,分时定价并不能实现燃气公司、工业用户等主体多方共赢,只能完成一方利益向另一方转移。总体而言,在一定条件下,在分时定价是削峰补谷,保障城市燃气管网稳定运营的有效措施,在分析分时定价政策时,须同时考虑上述因素才能更好地模拟市场运行情况。

基于时变价格弹性矩阵的深谷电价多目标定价策略

随着碳中和、碳达峰目标的提出,构建高比例新能源的新型电力系统已成为未来能源电力的发展形态,由此导致的高比例新能源渗透使系统净负荷曲线呈现剧烈的波动性和显著的深谷特征,对电力系统安全运行以及供需平衡提出了新挑战。为此,提出了一种基于时变价格弹性矩阵的需求侧深谷电价多目标定价模型。首先,确立基于模糊隶属度的深谷时段划分方法,并利用贝叶斯判别法对时段划分结果进行合理性评估。其次,针对用户需求响应的动态性,建立具有时变特征的价格弹性矩阵模型衡量用户的响应程度。最后,以用户满意度和系统峰谷差作为待优化的两个目标,建立多目标混合整数规划的深谷电价定价模型,并用非支配排序遗传算法求解模型并得到其Pareto最优解。为了检验所提模型的有效性,将其应用于中国华东地区某省的实际场景进行仿真分析。结果表明,上述模型可在高比例新能源渗透情景下降低峰谷差,促进用户用电行为向深谷时段转移,缓解电力系统在深谷时段的运行压力。

简易续约规则对谈判药品价格和持续供应的影响:现象及可行性方案探究

目的:探索在2022年医保目录简易续约背景下是否存在一类特殊现象,即部分药品会不断触发连续降价条件以致最终退出医保目录。方法:本文通过构建需求价格弹性模型,结合医保目录谈判和续约规则进行数值模拟,对多轮简易续约情况进行讨论,以验证简易续约规则是否影响药品可持续供应。最后,本文对可行性方案的适用条件进行数理分析。结果:在2022年简易续约规则下,市场上确实存在一类药品,当其首次医保谈判药品降价幅度和其弧弹性满足一定条件时,会陷入无限降价的困境。该现象可能是由于企业错估药品需求或是进入医保目录后药品销量飙升,量价线性关系被打破。减少续约次数和重新谈判能够降低此类现象发生的可能性。结论:2023年简易续约规则一定程度上避免了此类现象的发生,后续政策可将阶梯型降价标准改为连续型。

蓄热式电采暖参与消纳受阻风光的源荷协调滚动调度

蓄热式电采暖负荷具有时移性和连续可调性,可作为需求侧资源解决乡村地区新能源消纳困难与清洁供暖问题。当前实施的峰谷分时电价,不能根据源荷变化有效引导电采暖运行以消纳受阻风光。因此提出采用场景法描述风光荷的不确定性,根据源荷峰谷时段变化确定分时电价。并且考虑电采暖响应分时电价时出现用电同时率高问题,引入需求价格弹性系数,建立以蓄热式电采暖运行成本和系统负荷峰谷差期望最小的日前日内源荷协调优化模型,滚动调整每时段各灵活资源出力。最后,通过仿真验证模型的有效性。

基于弹性需求和动态定价的共享泊位分配

为解决共享车位管理中的车位分配与定价问题,考虑了价格变化对于用户不同停车时长选择的影响,分析在不同停车收费标准下用户停车时长选择的概率,并采用多项式拟合得到精细化的共享停车需求价格弹性函数。进而,为实现停车场价格的动态调整与车位分配,以平台收益最大与用户步行距离最小为目标,构建基于弹性需求和动态定价的泊位分配非线性混合整数规划模型,并设计了遗传算法。最后,设计了包含3个停车场共1000个泊位、共享平台运营时长为3 h的算例,对模型及算法加以验证,通过对比分析,基于弹性需求和动态定价的共享泊位分配方案相比于静态定价,实现平台收益增加19%且满足了大部分停车需求,说明动态定价下共享泊位分配模型及算法的有效性,为共享平台的车位管理提供了新思路。

小麦种子投入替代弹性度量分析

近年来,随着供给侧结构性改革的深入,小麦需求已由数量型向质量型转变,小麦种子改良可使生产质量大幅提升。以种子作为切入点,基于2005—2020年14个小麦主产区的各指标面板数据,采用超越对数成本函数模型,对小麦种子要素的需求价格弹性、替代弹性进行测算并分析各主产区差异。

基于动态分时电价引导的电动汽车需求侧响应

为激励电动汽车(electric vehicles,EVs)参与需求侧响应以减小电网负荷峰谷差,同时提高电动汽车用电经济性,首先,利用蒙特卡罗法模拟出电动汽车无序充电负荷,再根据电动汽车是否受电网调控或者受价格信号引导,将电动汽车分为3类进行处理;然后,以电网峰谷差均方值最小和用户充放电费用最小为目标,搭建基于电价需求弹性矩阵的动态分时电价(time-of-use,TOU)需求响应模型;最后,根据湖南某地区历史负荷数据对一天的电价进行分段,再通过仿真分析,验证考虑实时负荷反馈的动态分时电价可以有效地应对负荷波动,并且对于减小峰谷差和降低用户用电成本的效果更明显。

农业水价政策的节水效应——基于灌溉用水需求价格弹性的meta分析

中国农业水价综合改革已进入攻坚阶段,多种价格节水激励机制创新最终都绕不开农户对灌溉用水实际成本的直接反应,所以必须直面灌溉用水需求价格弹性问题。该研究基于1963—2022年全球范围内59篇文献中237个灌溉用水需求价格弹性的研究结果,通过meta回归分析方法,量化了导致灌溉用水需求价格弹性差异的主要因素,并分别通过价格水平和水价弹性区间的异质性效果探讨了农业水价政策的可干预空间。结果表明:①农业水价对灌溉用水需求价格弹性有正向影响,目前提高水价仍是农业节水的有效且稳健手段;且随着灌溉用水需求价格弹性区间的上升,提高水价对灌溉用水需求价格弹性的影响程度更大,提价节水效果更明显。②混合作物结构比单一作物结构更富有灌溉用水需求价格弹性,而高价值作物相对于低价值作物的灌溉用水需求价格弹性更小,说明提高水价对灌溉用水需求的抑制作用在种植混合作物或低价值作物时更容易实现;而且,种植混合作物时这一效应随着灌溉用水需求价格弹性区间的上升而更加显著,但对种植低价值作物农户而言,提高水价的节水效应在原有水价较高的情况下更显著。③相对单一水源灌溉而言,多水源联合灌溉条件下的灌溉用水需求对水价提高反应更敏感,且提高在用水源价格的节水效果有最佳水价弹性时机,同时也可能会促进新灌溉水源置换工程的实施。基于实证结论,为进一步深化中国农业水价综合改革和建设节水型社会,提供政策启示。该研究认为更应该强调灌溉用水的需求管理,提倡从灌溉用水需求对水价的反应程度来确定提高农业水价策略;根据地区种植结构,制定差异化农业用水提价方案;同时,在扩建灌溉水源工程论证阶段,加入基于灌溉用水需求价格弹性的科学用水预测。

考虑不同需求弹性的爬坡辅助服务市场出清模型

在新型电力系统建设背景下,高比例新能源出力间歇性和波动性给电网稳定和安全运行带来新的挑战,而提高电力系统灵活爬坡能力是应对新能源挑战的重要手段。为此,基于不同弹性的爬坡需求曲线,构建爬坡辅助服务市场出清模型,通过爬坡辅助服务市场激励灵活性爬坡资源建设,提升电力系统灵活爬坡能力。考虑不同区间的爬坡容量对电力系统的价值有所不同,建立不同需求弹性的爬坡需求曲线计算模型。在此基础上,设计了3种考虑不同爬坡需求弹性的爬坡与电能量市场联合出清模型,分析了这3种模型的爬坡影子价格定价方式及出清结果。构建算例展示弹性需求曲线计算方法及流程,基于IEEE 39节点系统对3种爬坡市场出清模型进行仿真分析。结果表明,增加爬坡需求弹性可提高系统整体运行的经济性。