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951.
In recent years, the traditionally pasture‐based dairy farms in New Zealand have become more intensive by using higher proportions of supplementary feed. This trend has been attributed to a range of factors, such as productivity enhancement, overcoming pasture deficits and the improvement of body condition scores. However, there is a lack of knowledge as to how feed use intensification affects the technical efficiency of dairy farms in New Zealand. This paper addresses the research gap by estimating the impact of feed use intensification on the technical efficiency of New Zealand dairy farms, using a fixed effects stochastic production frontier model and a balanced panel of 257 farms from 2010 to 2013. The empirical results show that technical efficiency on New Zealand dairy farms is positively and significantly influenced by feed use intensification, herd size and milking frequency.  相似文献   
952.
This paper contributes to the nascent literature on nowcasting and forecasting GDP in emerging market economies using big data methods. This is done by analyzing the usefulness of various dimension-reduction, machine learning and shrinkage methods, including sparse principal component analysis (SPCA), the elastic net, the least absolute shrinkage operator, and least angle regression when constructing predictions using latent global macroeconomic and financial factors (diffusion indexes) in a dynamic factor model (DFM). We also utilize a judgmental dimension-reduction method called the Bloomberg Relevance Index (BRI), which is an index that assigns a measure of importance to each variable in a dataset depending on the variable’s usage by market participants. Our empirical analysis shows that, when specified using dimension-reduction methods (particularly BRI and SPCA), DFMs yield superior predictions relative to both benchmark linear econometric models and simple DFMs. Moreover, global financial and macroeconomic (business cycle) diffusion indexes constructed using targeted predictors are found to be important in four of the five emerging market economies that we study (Brazil, Mexico, South Africa, and Turkey). These findings point to the importance of spillover effects across emerging market economies, and underscore the significance of characterizing such linkages parsimoniously when utilizing high-dimensional global datasets.  相似文献   
953.
954.
Economic variables usually follow a dynamic trend pattern. However, it is difficult to estimate this trend precisely as numerous economically- and statistically-based estimation methods exist. This contribution proposes a data-driven nonparametric trend that is local polynomial, to improve arbitrary trend estimations of commonly used methods concerning the selection of the smoothing parameter and the dependence structure. An iterative plug-in (IPI) algorithm determines the bandwidth endogenously and allows a theory-based interpretation of the length of growth processes. This length of the bandwidth reflects the lengths of the steady state periods. Consequently, the bandwidth identifies the time period of stable economic conditions and can detect economic changes. To demonstrate the power of this estimation approach, an extensive simulation study is performed. Furthermore, examples using US and UK GDP data along with a guide for the optimal choice of algorithms for empirical applications are provided. This proposed method yields new insights for growth dynamics, cyclical movements and their dependence.  相似文献   
955.
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   
956.
Estuaries provide advantageous sites for both harbors and fish habitats. In many countries, harbor expansion in estuaries contributed to the decline of fish populations with impacts at the global scale. Restoring these habitats is important to prevent a global biodiversity crisis but is costly and potentially unaffordable for polluters under the Polluter Pays Principle. Such affordability issues prompt decision-makers to reduce environmental targets of restoration programs. Harbor infrastructures destroy fish habitats but generate benefits for society and contribute to the public interest, raising some questions on who is responsible for environmental degradations and who can afford environmental restoration costs? One way to allocate restoration costs is to analyze the amount of harbor services consumed by economic sectors. This paper addresses these questions by computing burden sharing scenarios with an input–output matrix. These scenarios are simulated under the shared responsibility principle to distribute restoration costs among stakeholders in the Seine estuary, France.  相似文献   
957.
利用企业所得税分享改革构建强度倍差模型,使用1997—2012年全国地级市数据,检验了地方财政压力对于投资多样性的影响及相关传导机制。结果表明,地方财政压力不利于投资多样性的提高;在财政压力下,地方容易形成偏向房地产行业的投资倾向。然而,不同地区地方财政压力对投资结构的影响存在异质性。经济发展水平较低的地区在财政压力下更容易降低投资多样性;而经济发展水平高的地区应对财政压力时,更倾向于通过多元化投资的方式做大税基、减轻财政压力。优化分税制结构、建立地方性税种能缓解地方财政压力,对于改变地方“房地产集中型”投资结构有一定的积极作用。  相似文献   
958.
宋敏  史婷  王茜 《水利经济》2018,36(6):20-25
明确港口腹地演变趋势、分析港腹耦合协调度,对长三角地区港腹联动发展具有重要意义。量化港口系统—腹地系统综合指标评价体系,运用高斯烟羽模型在2006、2011、2016年3个时间节点上测算长三角地区主要港口影响强度,并对腹地范围进行划分,利用耦合协调模型定量分析港口系统和直接腹地经济系统耦合协调度。研究结果表明:长三角地区港口呈现"一超多强"的格局,以上海港为中心,各港口多极发展;港口腹地范围整体稳定,局部波动,上海港的边缘腹地不断缩减;港口与腹地的耦合协调度处于上升态势,宁波—舟山港腹耦合协调度最高。  相似文献   
959.
This paper challenges the conventional wisdom that assumes widespread shirking and inefficiency in agricultural production under the collective system in Maoist China, and attributes these problems to egalitarianism in labour remuneration and difficulties in labour supervision. Drawing on interviews with 131 former production team members from 16 provinces, this paper re‐examines the issue of work incentives by placing it in a historical and social context in which formal institutions, such as the different forms of collective organization, income distribution and state extraction, as well as informal institutions, such as indigenous social networks, communal norms and collective sanction, interacted with non‐institutional factors, especially local geographical, demographic and ecological conditions, to constrain and motivate Chinese villagers participating in collective production. The complexity and fluidity of this context gave rise to a multiplicity of patterns of peasant behaviour in team farming, which accounts for the contrasting performances of rural collectives in different areas and periods.  相似文献   
960.
This article studies poverty persistence and the role of social security programmes on poverty among elderly in the US. We use a Latent Markov model to disentangle unobserved heterogeneity and state dependence. Because of its dynamic nature, unobserved heterogeneity is modelled to vary over time. This allows to capture different latent states of poverty that change over time. Result indicates the existence of three unobserved types evolving over time according to their propensity to be poor. Moreover, a strong persistence in poverty especially for women, individuals living alone and ethnic minorities is found. Finally, the estimates indicate that giving social assistance tends to reduce poverty.  相似文献   
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