Household size and residential water demand: an empirical approach*

The effectiveness of pricing policies depends on the price elasticity of consumption. It is well documented that residential demand for water is influenced by heterogeneity associated with differences in the size of the household and socioeconomic characteristics. In this paper, we focus on household size. Our initial hypothesis is that users’ sensitivity to changes in price is different depending on the number of household members. To this end, we carry out an empirical estimation of urban water demand in Zaragoza (Spain) distinguishing between households with different sizes using data at the individual level. As far as we are aware, this approach to urban residential water demand is new in the literature. The analysis suggests that all households are sensitive to prices regardless of size. A more relevant finding is that small households are more sensitive to price changes.     

农业两部制水价改革的福利效应分析

介绍了我国农业水价制度的变迁及农业水价的制定方法。分析了我国农业水价改革的水价福利效应。以湖北灌区农业水价改革为例，分析了农业水价改革的实践效果及改革中存在问题的成因。分析结果表明：农业水价改革强化了农田灌溉中的水量限制，而忽视了既定制度约束下农民用水的需求理性和灌溉系统脆弱的供水能力；农业两部制水价改革加剧了灌溉供水的时间需求与灌溉系统输配水能力之间的矛盾，导致农业灌溉水供求脱节、水资源利用率下降，难以达到节约用水和改善水资源分配效应的预期目标；完善水价形成机制、推进用水交易合约化是水价改革成功的关键。     

Station level gasoline demand in an Australian market with regular price cycles*

Regular and frequent gasoline price cycles are being observed in many Australian and Canadian markets. What is driving these price cycles has been the subject of academic studies and government investigations. The existing explanations for these price cycles all rely on the presumption that drivers are intensively sensitive to gasoline price differentials at the station level. However, no empirical evidence exists in the literature to support this presumption. This paper provides the first piece of empirical evidence. This paper uses a unique price and quantity data set and novel instruments to estimate the station level gasoline demand in the cycling market of Perth, Australia. The elasticity estimates confirm that drivers in the Perth area are indeed very sensitive to gasoline price differentials.     

水价对中国北方城市居民用水需求影响分析

介绍城市居民用水需求变化的背景,对北方城市居民用水需求进行了预测。得出结论：水价对于减少城市居民用水需求的作用非常显著;城市化的高速发展会对城市居民用水造成巨大压力,对城市居民用水价格、用水管理手段和农业节水制度的积极改革,为解决城市居民用水供需缺口提供可能。     

城市居民用水需求影响因素研究

介绍城市居民用水需求影响因素研究的背景,定性分析城市居民用水需求的影响因素,分析城市居民用水量的影响因素计量模型。确定影响城市居民水资源需求的主要因素：水价的提高会对减少城市居民用水数量;水资源的短缺状况会显著降低城市居民用水量;城市居民家庭用水存在规模效应;城市用水人口素质越高,人均年用水量越多。得出结论：通过运用价格机制,改革用水制度,可以调动人们节约用水的积极性;采用更为节水的生产技术,会大大消除水资源供求缺口,其成本也可能大大低于调水方案。除此之外,城市居民的社会经济特征也会影响到城市居民用水量,例如家庭平均人口数以及受教育人口比例等。     

从贡献分析法谈林产品生产企业的价格调整策略

本文讨论林产品企业在生产相关林产品时价格调整策略,从贡献分析法的角度,建立了调整策略的数学模型并给出了一个例子。     

海南省水资源供需分析

阐述海南省水资源的特征及变化趋势,并针对水资源供需中存在水资源开发利用率低,用水效率不高,水环境污染和水资源供需矛盾大等问题,提出保障水资源供需的战略措施,即建立新型水资源价值体系、水资源供需保障体系、水资源供需集团化与规模化经营体系和水资源安全保障体系等。     

沈阳市城镇居民生活用水需求影响因素分析

利用时序数据及沈阳市康平县城镇居民生活用水的截面数据,对沈阳市城镇居民生活用水需求的影响因素进行实证分析,估计其需求价格弹性、需求收入弹性及需求教育弹性。估计结果明显有别于其他地区的研究结果,建议沈阳市应根据城镇居民生活用水水价偏低、收入弹性较大的实际,同时考虑到居民的承受力,调高水价时采用递增的阶梯式水价或补贴低收入用水户等政策,合理发挥价格杠杆的作用,同时还应注意到负的需求教育弹性,加强对居民的节水宣传教育。     

The impact of drought and water scarcity on irrigator farm exit intentions in the Murray–Darling Basin

Drought and future water scarcity in the Murray–Darling Basin (MDB) will continue to restructure the irrigation industry in the coming decades. There has been little work conducted in Australia that has modelled farm exit or exit intention. ABARES farm survey data were used to model irrigators’ farm exit intentions across the southern MDB from 2006 to 2013. In particular, we examined the hypotheses that drought and water scarcity positively impacted on farm exit intentions and that it is the poorest performing farms that intend to exit in times of drought. Results revealed that water scarcity impacts varied considerably. There was only weak evidence to suggest that irrigators’ exit intentions were higher in times of drought, but there was stronger evidence to support the influence of a lagged water scarcity impact on farm exit intentions during periods of nondrought (e.g. intending to exit at times when the property market was less depressed). There was also strong evidence that poorer performing farms (measured by rates of return and higher debt over a certain level) were more likely to have exit intentions in drought periods, but not necessarily so in nondrought periods. Older age is the most consistent predictor of farm exit intentions across all industries, though it was most significant in drought periods.     

区域水资源供需的系统动力学仿真

以广东省北江下游影响区为研究范围，基于系统动力学的理论和方法，按照科学发展观的要求，应用系统分析、可持续发展的思路，在系统分析区域水资源供需系统各要素之间及其与人口、经济、社会、生态环境等发展之间互动影响关系的基础上，建立区域水资源供需的系统动力学模型，并进行了动态仿真模拟，认为GDP增长受到水资源不足的制约，因此，在追求经济效益的同时，必须考虑到水资源的可持续利用，而不是“掠夺式”利用，注重GDP增长速度与环境保护的协调发展。     

中国主要木材产品的需求收入弹性测算与启示

木材产品是重要的林产品,是国家经济建设和人民生活主要的资料,在国民经济与社会发展中发挥积极作用。通过构建双对数模型,采用实证分析的方法,估算出2005²012年间原木、锯材和人造板这三种木材林产品的平均需求收入弹性分别为0.301、1.100和1.338,总结出中国木材产品消费和国民经济增长的作用规律,并得到加速森林资源培育、继续优化产业结构和建立可持续贸易机制几点启示。     

Economic assessment of acquiring water for environmental flows in the Murray Basin*

This article is an economic analysis of reallocating River Murray Basin water from agriculture to the environment with and without the possibility of interregional water trade. Acquiring environmental flows as an equal percentage of water allocations from all irrigation regions in the Basin is estimated to reduce returns to irrigation. When the same volume of water is taken from selected low-value regions only, the net revenue reduction is less. In all scenarios considered, net revenue gains from freeing trade are estimated to outweigh the negative revenue effects of reallocating water for environmental flows. The model accounts for how stochastic weather affects market water demand, supply and requirements for environmental flows. Net irrigation revenue is estimated to be 75 million less than the baseline level for a scenario involving reallocating a constant volume of water for the environment in both wet and dry years. For a more realistic scenario involving more water for the environment in wet and less in dry years, estimated net revenue loss is reduced by 48 per cent to 39 million. Finally, the external salinity-related costs of water trading are estimated at around 1 million per annum, a quite modest amount compared to the direct irrigation benefits of trade.     

Classifying households for water demand forecasting using physical property characteristics

Changes in population distribution across Europe are driving the construction of substantial numbers of new houses, creating a need to forecast water demand for new housing developments. The most certain information available on new households during planning are the physical characteristics of the properties themselves. This paper sets out to establish how to classify properties in terms of their physical characteristics for the purpose of forecasting water demand. Analysis of household water demand under a univariate classification of property type showed significant differences for properties of different size (number of bedrooms), architectural type (e.g. flats vs. terraced) and garden presence but not for age or for garden aspect. Analysis of household water demand under a multivariate classification of property type showed fewer significant differences between property types. The results of the study were compared to studies and found to fit qualitatively. However, quantitative differences were noted indicating geographical and sampling variation which requires further investigation. In addition, further research is required to determine the relative certainty of forecasts derived from physical vs. socio-economic or demographic characteristics.     

供水保证率法在水利工程水价核算中的应用

针对水利工程水价核算采用按设计供水保证率法分摊同一工程、不同供水类别的成本费用存在的不足,提出用实际供水保证率取代设计值的水价核算方法,并以引滦枢纽工程为例,计算了该工程的实际供水保证率,分析了不同供水保证率对水价核算水平的影响,指出水管单位应开展实际供水保证率测定工作,从而使我国供水工程水价核算工作更加科学、合理、符合实际。     

Urban water demand with fixed volumetric charging in a large municipality: the case of Brisbane,Australia*

This paper uses suburb‐level quarterly data to model residential water demand in Brisbane, Australia, from 1998 to 2003. In this system, residential consumption is charged using a fixed annual service fee with no water entitlement followed by a fixed volumetric charge per kilolitre. Water demand is specified as average quarterly household water consumption and the demand characteristics include the marginal price of water, household income and size, and the number of rainy and warm days. The findings not only confirm residential water as price and income inelastic, but also that the price and income elasticity of demand in owner‐occupied households is higher than in rented households. The results also show that weather, particularly summer months and the number of rainy days, exerts a strong influence on residential water consumption.     

The income elasticity of meat: a meta‐analysis

The demand for meat has been estimated by many studies utilizing various data and estimation methods. In this study, we perform a meta‐analysis of the income elasticity of meat that involves regressing 3357 estimated income elasticities, collected from 393 studies, on variables that control for study characteristics. Across several meta‐regression specifications, we find significant differences in income elasticities tied to the type of meat being studied, as well as a few functional forms, data aggregations, publication characteristics, and locations of demand. However, many study characteristics do not significantly influence reported income elasticities. Less concern should be given to such characteristics when choosing an income elasticity from the literature.     

溧水县水资源供需分析

针对溧水县水资源特点,分析水资源现状。结合节水型社会建设的要求,采用相应的定额,分析预测了各行业需水量和供水量,分析不同平衡分析方案的缺水度。分析表明,在一次平衡方案下,溧水县近期和远期缺水度均大于30%,处于严重缺水状态。在二次平衡方案下,可以有效地解决缺水问题。     

供水价格的影响因素分析

简述影响水价的自然、社会、工程和环境因素,探讨水价成本测算、水价制定及执行的目标和原则。     

Alternative Methods for Estimating Price Elasticities of Imports

Abstract

This article compares three commonly-used methods for estimating import price elasticities: (1) trade-weighted price elasticities of domestic demand and supply along with price transmission; (2) direct estimates based on ad hoc import demands; and (3) Armington model estimates. Using data from El Salvador's grain markets (white maize, red beans, and rice), the results indicate that the second method provides the most reliable estimates and that the Armington procedure may not be appropriate for estimations of this type. However, the first method offers the best guesstimates to assess potential rather than historical import response as trade is liberalized.     

乐亭县水资源配置研究

分析了乐亭县水资源条件及开发利用现状,对不同时期的需水量和供水量进行预测,制定了多水源供水方案,提出了水资源合理配置结果。