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11.
[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   
12.
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   
13.
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   
14.
Sporadic studies on the global norm of national treatment for patent uncertainties (NTPU) urge for insights of changes as well as for clarification to discrepancy. This global norm has been a concern for policy makers and practitioners for over a century, as a socially and strategically more significant matter than before for multilateral cooperation given the active technology transfer across borders. To fill in the void and extend prior studies, we examine the global compliance of NTPU from the perspective of patent pendency and granting by addressing three relevant questions: (1) Is NTPU upheld within countries? (2) How does NTPU diverge across countries? (3) How does NTPU change, as an outcome, over time? Based on the institutional theory, lagged regression modeling and longitudinal comparison of US and Chinese patenting, our findings reveal that: (1) NTPU is overall upheld because equality in pendency is demonstrated in both countries and in US granting, and foreigners are even favored for Chinese granting. (2) NTPU is comparatively divergent between the countries in pendency and granting due to national variations. (3) Regressive and progressive changes in NTPU are evidenced since both countries provide equal or higher granting, but longer pendency than before. Our findings contribute to theories by providing new insights to the global norm of national treatment and institutional theory from the perspective of patent uncertainties. We make novel empirical contribution to address NTPU changes of the top patent filing countries and methodological contribution to the longitudinal comparative study. The results also provide implications that concern policy makers and practitioners to handle patent uncertainties across borders.  相似文献   
15.
Mobile channel additions have been shown to increase consumer-brand relationships, brand satisfaction towards and overall purchasing from a retailer, but what is less apparent is whether shareholders are fully rewarded for retailers’ mobile channel additions. Results from an event study on 115 announcements relating to mobile app additions of publicly traded U.S. retail firms between 2009 and 2016 indicate that the stock market responds generally positively to mobile app additions, but specifically to the two mobile app addition types. Stock market responses to search-related and purchase-related app additions are moderated by firm size, product category, and target customer age. For announcements of search-related apps, the market responds more positively to product retailers than to service retailers, and to small firms than large ones. For announcements of purchase-related apps, the market responds less positively to firms that target younger customers than firms who do not especially target them.  相似文献   
16.
The main objective of this paper it to model the dynamic relationship between global averaged measures of Total Radiative Forcing (RTF) and surface temperature, measured by the Global Temperature Anomaly (GTA), and then use this model to forecast the GTA. The analysis utilizes the Data-Based Mechanistic (DBM) approach to the modelling and forecasting where, in this application, the unobserved component model includes a novel hybrid Box-Jenkins stochastic model in which the relationship between RTF and GTA is based on a continuous time transfer function (differential equation) model. This model then provides the basis for short term, inter-annual to decadal, forecasting of the GTA, using a transfer function form of the Kalman Filter, which produces a good prediction of the ‘pause’ or ‘levelling’ in the temperature rise over the period 2000 to 2011. This derives in part from the effects of a quasi-periodic component that is modelled and forecast by a Dynamic Harmonic Regression (DHR) relationship and is shown to be correlated with the Atlantic Multidecadal Oscillation (AMO) index.  相似文献   
17.
In order to deliver public value, the UK government sought to build relationships and connect ‘the public’ with public servants (including back-office workers), but with what effect? Drawing on interviews with public service accountants, the authors found that how these accountants conceptualized ‘the public’—as society or people—shaped whether public value was considered as a monetary or moral concept. Accountants who regarded the public as people spoke of an improper level of involvement and struggled to maintain their professionalism.  相似文献   
18.
The Chinese high-tech industry has developed greatly since the beginning of China's “National High-tech R&D (863) Program” and “China Torch Program”. This paper introduces a conceptual model extended from the innovation value chain model to simultaneously estimate the R&D and commercialization efficiencies for the high-tech industries of 29 provincial-level regions in China. To match reality, a network DEA incorporating both shared inputs and additional intermediate inputs is constructed to open the “black box” view of decision making units used in single-stage DEA. This study is the first attempt to link the R&D and commercialization with a solid theoretical foundation and feasible mathematical methods. The empirical findings show that most of the 29 regions have low efficiency in the commercialization sub-process compared to the R&D sub-process, although there are regional differences in China's high-tech industry. Pearson correlation shows that the R&D sub-process is not closely correlated to the commercialization sub-process in terms of efficiency. Our analysis can provide information for the formulation of policies to achieve high innovation efficiency.  相似文献   
19.
以A股地方国有上市公司为研究对象,从投资效率的角度考察国有资本经营预算制度的实施效果,并进一步检验其对企业价值的影响。研究发现,国有资本经营预算能够显著抑制地方国有企业的非效率投资,尤其是抑制过度投资行为,并且这种影响对处于市场化程度较低地区的地方国有企业更加显著。进一步研究发现,国有资本经营预算能够通过抑制非效率投资来促进地方国有企业价值的提升。  相似文献   
20.
江西省农村土地利用变化及生态系统服务价值研究   总被引:2,自引:0,他引:2  
[目的]土地利用变化及生态系统服务价值研究一直是土地资源评价与管理方面的热点研究问题,通过对江西省土地利用变化和生态系统价值进行研究,为江西省土地规划和资源的可持续利用提供理论依据。[方法]文章基于文献查阅的方法,利用多样性指数模型、土地利用动态度和生态系统服务价值模型,结合2009~2016年江西省农村土地利用的现状及变化,分析了其生态系统服务价值及相应变化。[结果]近年来,江西省农村土地利用程度高、多样性指数中等且呈先下降后上升的趋势。土地利用类型的面积与该土地利用类型的生态系统服务价值呈同向变化的关系。通过对土地利用类型的ESV值进行分析,发现农村土地利用的生态系统服务功能价值总体在减少;对单项生态系统价值分析,水源涵养在江西省农村土地生态系统服务中占有最重要的地位。[结论]2009~2016年江西省农村土地利用结构都发生了变化,生态系统服务总价值出现了降低趋势,各单项生态系统服务功能价值也在减少,土地利用结构对生态系统功能价值具有决定作用。因此,政府应该合理利用土地,保护生态系统,协调好环境与经济发展的关系。  相似文献   
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