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21.
[目的]在耕地保护形势日趋严峻的情形下,开展耕地生态价值补偿量化研究对了解耕地外部性价值的大小及深化耕地生态价值的量化方法和思路具有重要意义。[方法]文章以新疆为例,从14个地州市的耕地生态服务价值出发,将生态超载指数作为耕地生态服务价值与生态足迹在各地州市转移的测度,同时综合考虑各地州市的经济发展状况,通过构建市域生态价值补偿量化模型分别测算各地州市耕地生态价值补偿量。[结果](1)2015年新疆耕地生态服务价值整体上有盈余输出,全疆共可获得生态补偿费103.31亿元;(2)2015年新疆南北疆耕地生态服务价值比为1:1.7,生态足迹总量比为1:2.2,生态超载指数北亏南盈,表明南北疆耕地生态足迹和耕地生态服务价值间呈"空间异位"格局;(3)新疆北疆乌鲁木齐市、克拉玛依市、吐鲁番市及哈密市共需支付耕地生态补偿费55.67亿元,北疆(乌鲁木齐市、克拉玛依市、吐鲁番市及哈密市外)和南疆地区分别可获得生态补偿费为96.59亿元和62.39亿元。[结论]该文可为新疆各地州市构建耕地生态价值补偿路径提供新思路,也可为以耕地生态价值量确定耕地保护指标和构建耕地生态补偿机制提供参考。  相似文献   
22.
Former politicians on the board of directors bring to the firm domestic political connections and political knowledge. Previous research has mainly highlighted the role of contacts, without fully recognizing the role of political knowledge accumulated at home. By focusing on the effect of domestic political connections on foreign direct investment, we show that domestic political knowledge also shapes foreign expansion. We argue that contacts provided by former politicians may not be useful for foreign expansion whilst their political knowledge can be of help in countries with discretionary governments and with similar institutional environments to the one of the home country.  相似文献   
23.
The paper examines Russia’s international image and its influence on investment by Russian companies in post-socialist Europe. Findings are based on the cases of Gazprom’s South Stream Pipeline project, and Sberbank’s acquisition of Volksbank’s Central and Eastern European assets in Hungary and Serbia. The paper demonstrates that international positions and economic interests of two countries determinate decisions regarding investments of Russian companies, while Russia’s image to some extent accelerates these decisions in Serbia. The paper is based on the results of interviews with representatives of business communities conducted in Hungary and Serbia in 2012–2017, professional reports, and official documents.  相似文献   
24.
We model market integration in the Middle East and Africa by analyzing price dispersion and testing the law of one price (LOP) on highly-comparable actual local retail prices of 135 goods and services across 23 countries in the region over the period of 1990–2016. Second-generation panel estimators are applied to four price benchmarks: Regional average, South Africa, China, and US prices. Cross-regional price dispersion diminishes considerably over time up to 2008, particularly for non-tradeables around China price. The test of LOP indicates the percentage of convergent prices is highest in China price benchmark, followed by US, South Africa, and regional average benchmarks. Direct estimation of the convergence speed confirms this order. Overall, the results show evidence of increasing market integration in Middle East and Africa but it appears to be driven by global forces and, especially, the rise of China as a new economic power. The results show that some emerging market economies, such as China, can step up and promote integration while traditional economic powerhouses, such as the USA and UK, disengage from international economic relations.  相似文献   
25.
Models of cities based on conventional spatial market theory are unable to replicate a realistic size distribution. The stochastic process approach to size distribution, which assumes proportionate growth, does not provide an economic foundation for spatial trades. There is an apparent irreconcilability. We propose that since there is a continuum of equilibria in models of spatial markets with endogenous location, proportionate growth can work as equilibrium selection. We present computations for an urban configuration that has not been presented in the literature before. A small city locates inside a larger city's agricultural supply zone. This generates a larger variation in city size that may include a realistic size distribution.  相似文献   
26.
This paper presents a new facility location problem variant with application in disaster relief. The problem is unique in that both verified data and unverified user-generated data are available for consideration during decision making. The problem is motivated by the recent need of integrating unverified social data (e.g., Twitter posts) with data from more traditional sources, such as on-the-ground assessments and aerial flyovers, to make optimal decisions during disaster relief. Integrating social data can enable identifying larger numbers of needs in shorter amounts of time, but because the information is unverified, some of it may be inaccurate. This paper seeks to provide a “proof of concept” illustrating how the unverified social data may be exploited. To do so, a framework for incorporating uncertain user-generated data when locating Points of Distribution (PODs) for disaster relief is presented. Then, three decision strategies that differ in how the uncertain data is considered are defined. Finally, the framework and decision strategies are demonstrated via a small computational study to illustrate the benefits user-generated data may afford across a variety of disaster scenarios.  相似文献   
27.
面源污染视角下江西省耕地利用效率研究   总被引:1,自引:0,他引:1  
[目的]在面源污染视角下考察耕地利用效率,可以为推动耕地可持续利用提供理论和参考依据。[方法]文章基于2000—2014年我国13个粮食主产省(区)耕地投入产出的面板数据,运用SBM方向性距离函数将耕地面源污染因素纳入到传统的效率分析框架,从省际比较的维度对江西省耕地利用效率进行了测度与分析。[结果]考虑面源污染因素对耕地利用效率测算产生了一定的影响;江西省耕地利用效率值呈现阶段性特征,耕地利用效率排名比较稳定,近年来排名有上升趋势;江西省耕地利用绩效一般,且与最佳实践者存在较大的差距。[结论]忽视面源污染因素的耕地利用效率评估是失真和不符合实际的,宜将面源污染因素纳入到耕地利用效率的测度框架,以此来更科学地量化评估耕地利用绩效;设计和完善相关政策,以有效控制耕地面源污染;加强与先进省(区)的交流与合作,学习其农业可持续耕作技术与管理经验,进一步推动江西省耕地产出与资源、环境协调发展。  相似文献   
28.
This article sheds light on the underlying mechanisms behind the changes in the value relevance of accounting information in the Karachi Stock Exchange (KSE) during the 1999–2010 period. We find that neither changes in earnings quality nor the earnings lack of timeliness hypothesis can explain the decline in the value relevance of accounting information in the KSE. Based on the stylized facts associated with the growth of the KSE and the broader economics literature, we argue that the reduction in the explanatory power of accounting information vis-à-vis stock returns was caused by herding behaviour. Empirical estimates from state-space model of herding behaviour confirm the existence of herding, and we find that the value relevance of accounting information is significantly lower in periods characterized by herding behaviour. This article is also amongst the first attempts to empirically demonstrate that an expansionary monetary policy and increases in foreign portfolio investment lead to increased levels of herding.  相似文献   
29.
The purpose of this article is twofold. First, we examine if, and to what extent, a general Kaleckian analysis of the potential effects of financialisation on income shares in advanced capitalist economies is of relevance for the three Eurozone countries under investigation—France, Germany and Spain—in the period before the recent financial and economic crisis. Second, we study changes in the financialisation–distribution nexus that have occurred in the course of and after the financial and economic crisis. We find that the countries examined here have shown broad similarities regarding redistribution before the crisis, although there are some differences in the underlying determinants. These differences have continued during the period after the crisis and have led to different results in the development of distribution since then.  相似文献   
30.
Integrating signalling theory and the portfolio diversity literature, we theorize that diversity in a firm's patent and alliance portfolios sends contrasting flow signals impacting its market value in a nuanced way. Diversity in an alliance portfolio mediates the patent portfolio diversity – market value relationship by suppressing the negative effect of patent portfolio diversity creating an overall positive effect. We test our mediation model on a longitudinal set of 225 US biopharmaceutical firms that were awarded 17,078 patents and participated in 37,744 alliances between 1990 and 2006. Our theory and findings contribute three novel insights. First, we demonstrate the value of a temporal lens in explaining why diversity in a firm's patent and alliance portfolios send flow signals that establish expectations among market observers and have performance implications. Second, establishing that patent and alliance portfolio diversity are temporally sequenced provides compelling evidence for the value of studying multiple types of portfolios, their temporal relationships and effects on firm outcomes. Third, since diversity in a firm's portfolios can send contrasting flow signals conditioned on the cognitive demands and proximity involved in interpreting the signals, firms that do not maintain a ‘signalling fit’ with market observers increase the probability of unintentional negative signalling effects.  相似文献   
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