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1.
应用碳氧平衡法测算生态用地需求量实证研究   总被引:13,自引:0,他引:13  
研究目的:应用碳氧平衡法探讨区域生态用地需求量的测算方法,为编制土地利用总体规划提供科学依据。研究方法:碳氧平衡法,生态服务功能法。研究结果:空气中的碳氧平衡是在不断调整绿色植物和多种释碳耗氧关系基础上实现的。研究二氧化碳和氧气的消耗与供应关系及其分配特征,有助于测算生态用地需求量。应用上述方法开展了测算郑州市2010年生态用地需求量实证研究。研究结论:解决生态用地需求量预测必须界定"生态用地"的概念和区分土地生态功能多元性。研究表明基于碳氧平衡法测算区域生态用地需求量的方法是可行的,具有可操作性。应当从生态用地角度重新审视土地利用现状分类体系,使其完善。  相似文献   

2.
Household size and residential water demand: an empirical approach*   总被引:1,自引:0,他引:1  
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.  相似文献   

3.
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.  相似文献   

4.
从铅山县“十一五”期间占用征收土地情况和占用征收林地情况,分析林地变化的成因和趋势,从而推算铅山县在2011-2020年随着经济的快速增长其土地和林地总的需求量。  相似文献   

5.
白洁 《现代食品》2020,(6):22-23
近年来,国内经济发展迅速,人们生活水平也得到很大提升,使得人们越来越重视安全,而食品是人们生活中的基本物质保障,是人们生活的必需品,所以食品的质量与安全问题是当下最热门的话题之一。当前消费者的需求会受食品质量与安全的影响,频发的食品质量与安全问题让人们愈发重视食品质量与安全,消费者的需求渐渐发生变化。基于此,本文展开了关于食品质量与安全对消费者需求的影响的研究。  相似文献   

6.
This article offers an analytical framework for studying consumer demand for food quality based on a theory‐consistent demand model, namely, the Exact Affine Stone Index specification. Importantly, it accounts for unobserved consumer and regional heterogeneity, and allows for arbitrary Engel curves. The empirical value of our framework is illustrated in an econometric analysis of demand for food quality in China. Evaluating possible structural changes in consumer food expenditures in China is of paramount importance, given the ever‐increasing global role of China and the implications of the structural food preference changes for the global food system. The major findings emerging from this study indicate that income is an important determinant of demand for food quality and quantity with the relatively more affluent provinces having a higher affinity for food quality.  相似文献   

7.
建设用地需求量预测是土地利用总体规划修编的重要组成部分,选用合理的方法准确预测规划目标年的建设用地需求量具有重要意义。分析比较了双因素预测法、趋势预测法和GM(1,1)模型法预测建设用地需求量的特性与适用条件,以广西壮族自治区永福县为例,对建设用地需求总量预测进行了实证研究。结果表明:GM(1,1)模型法在县域建设用地需求量预测中具有较好的精度,更符合县域经济的发展。该研究成果可为新一轮土地利用总体规划修编中建设用地趋势变化分析以及需求量的确定提供借鉴参考。  相似文献   

8.
A generalized version of a well-known statistical result is used to suggest an alternative strategy for estimating nested constant elasticity of substitution preferences for recreation demand. Parameter and welfare estimates from nested constant elasticity of substitution count data demand system models are presented and compared to estimates from the multinomial approaches developed previously. A significant advantage of the count data estimation strategy over the multinomial-based approaches is that the analyst avoids the difficulties associated with choice occasion specification and interpretation.  相似文献   

9.
Understanding the role of health information in food and nutrient demand has become an important issue over the last decade. Endogeneity and measurement error are two empirical problems that are inherent in this type of analysis. While some type of instrumental variables estimation would appear the obvious solution, this article provides several theoretical and empirical reasons why this is not the case in cross-sectional analysis. An alternative estimation strategy is pursued, an empirical example is given, and the implications are discussed.  相似文献   

10.
对天津市用水需求和供水能力进行分析估算。结果表明:为填补水资源供需缺口,预计到2020年,全市对海水淡化水的需求量约为3亿m3,海水淡化工程规模将达到80万t/d。根据海水淡化水用途,运用比例分摊、生产函数等计算方法,量化测算得海水淡化水用于居民生活、工业生产和浓海水综合利用的经济价值分别为39.75元/m3、96.8元/m3和2.7亿元/a。研究成果旨在为充分认识海水淡化水的经济效用和价值,科学决策海水淡化产业发展提供参考。  相似文献   

11.
Pre‐committed consumption represents the portion of demand that is determined by non‐price and non‐income factors. This study uses quarterly data to estimate a Generalised Almost Ideal Demand System (GAIDS) to test for the existence of pre‐committed meat consumption in Australia. Two specifications are estimated to evaluate the impact of seasonal and time trend factors on pre‐committed demand. Evidence is found for the existence of pre‐committed chicken consumption when jointly estimated with seasonal and time trend factors. Results support improved demand modelling of Australian meat consumption using the GAIDS and provide insights into how Australian meat demand is affected by price, expenditures, pre‐committed consumption, seasonality, and trends.  相似文献   

12.
首先,在梳理了相关文献的基础上,归纳总结了森林碳汇的相关概念、森林碳汇的计量方法、森林碳汇的效益。其次,阐述了中国森林碳汇市场需求不足的现状。再次,对森林碳汇需求及其影响因素进行研究分析。其中,企业森林碳汇需求主要受内部特征因素、外部动力因素和市场机制三大因素影响;社会公众需求主要受个人特征因素、主观意识因素和外部条件因素三大因素影响。最后,提出要加强森林碳汇需求方面的研究等建议。  相似文献   

13.
Few studies have been performed to use the detailed healthy eating index (HEI) to estimate consumer demand for diet quality. In this article, we apply household production theory to systematically estimate consumer demand for diet quality using the HEI developed by the U.S. Department of Agriculture. The results show that consumers have insufficient consumption of food containing dark green and orange vegetables, legumes and whole grains. Age and education have a significant impact on consumer demand for diet quality, but income does not. The own‐price elasticities of demand for diet quality are inelastic. Simulation of tax scenarios indicates that a tax on sugar‐sweetened beverage may be more efficient than a tax on fats, oils and salad dressing in improving consumer diet quality. This information is critical for policies and programs that are designed to improve healthy food choices, thereby reducing the social cost of public health.  相似文献   

14.
The article develops an alternative econometric methodology to estimate a system of censored demand equations using a large cross-section data from Colombian urban households. The approach preserves the behavioral information expressed by zero expenditures and conforms with the requirements imposed by consumer theory in a way consistent with the random utility hypothesis. We motivate the choice of the Tobit model as a statistical representation of consumer behavior and introduce the methodology by specifying the AIDS model modified according to both a translating and scaling demographic transformation. We propose to estimate each demand equation in unrestricted form using the jackknife technique. We then recover the demand parameters imposing the cross-equations restrictions by using minimum distance estimation. The empirical results of the censored demand system for specific households of policy relevance are reported.  相似文献   

15.
For three years in Bolivia (2002–2005) the INNOVA Project finished researching several technologies for sustainable agriculture, started by earlier DFID-funded projects. Before INNOVA started critics suggested that these technologies should be discarded in favour of a demand survey. Instead, INNOVA kept the existing technologies, but judged the demand for them with several methods (CIAL, sondeo technology fair, and others). INNOVA found that there was demand for some of the technologies, but that a survey would have missed much of the demand, which is implicit. That is, people are not initially aware of all their problems or of all the possible solutions. Over the years, farmers made more specific, sophisticated demands on the technologies, which evolved as a result. Demand and supply of farm technology are like two sides of an unfolding conversation.  相似文献   

16.
This article deals with the specification of a locally flexible and theory-consistent system of mixed demand functions, a framework that allows for a rich set of possibilities about what is assumed as exogenous in a demand model. A coherent mixed demand system is derived by using the restricted expenditure function typically studied in the related area of rationed demands. The method is implemented by a new normalized quadratic (NQ) parameterization of the restricted expenditure function. The resulting NQ mixed demand system is illustrated with an application to a nine-good model of the Italian demand for vegetables.  相似文献   

17.
Quantifying the structure of food demand in China: An econometric approach   总被引:1,自引:0,他引:1  
This article examines food demand structure and its dynamics for 11 commodities in urban China. The analysis is based on household‐level expenditure survey data for two cross‐sectional surveys of Chinese households pertaining to food expenditure patterns during 1995 and 2003. Pre‐committed components of commodity demands, that are insensitive to economic variables, are explored. We use the generalized quadratic almost ideal demand system (GQAIDS) for its empirical superiority to the generalized almost ideal demand system (GAIDS), and estimate the associated parameters via full information maximum likelihood procedure (FIML) accounting for endogeneity of total expenditures on food for home consumption (FAH). We also use quality‐adjusted commodity unit values to control for quality differences resulting from commodity aggregation and food choice. Furthermore, we derive GQAIDS elasticity formulas, and estimate income elasticities without restrictions. The results partially support the hypothesis that an average Chinese household has incorporated elements of Western diet (fine grains) into traditional Chinese food diet over time. Moreover, the outcome of a simple test developed here points to possible preference changes for a majority of food staples under study.  相似文献   

18.
海南省水资源供需分析   总被引:3,自引:1,他引:3       下载免费PDF全文
周祖光 《水利经济》2005,23(3):47-49
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。  相似文献   

19.
粮食安全问题是目前城镇化进程中的风险之一.通过分析后认为,城镇化过程中粮食总体消费弹性区间呈收窄趋势,粮食刚性需求越来越大,这一现象在城镇地区相较于农村地区更为显著.其次,虽然粮食产量持续增长,但由于不确定性的增多,农产品供给难以保持与需求同步增长,一旦发生粮食减产,势必从多方面威胁到我国的经济形势.  相似文献   

20.
沈阳市城镇居民生活用水需求影响因素分析   总被引:3,自引:0,他引:3       下载免费PDF全文
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。  相似文献   

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