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1.
Programs to improve water quality do not improve all water bodies equally. Evaluation of the benefits of such programs must account for where improvements occur and the relative magnitude of improvements that occur in different places. This study uses a choice experiment survey to explore how the value to a household of a surface water quality improvement varies as a function of (i) the distance between the household and the affected streams and rivers, (ii) the degree to which the quality of the water has been improved, (iii) how many stream and river miles have been improved, and (iv) the sizes of the affected streams and rivers. Results show evidence that value declines with distance in an approximately linear way, weak evidence that large rivers are worth more than small rivers, and no evidence that willingness-to-pay is nonlinear in either the degree of water quality improvement or the number of stream miles improved. These results indicate that it may be defensible in applied work to value small, spatially-explicit water quality improvement projects independently and then sum over projects.  相似文献   
2.
为了实现产品生产阶段到服务阶段业务与数据的有效集成,从业务层和数据层对制造服务系统中的大修维护维修(MRO)与企业资源计划(ERP)的集成过程进行了建模与分析,对ERP与MRO系统之间的业务过程和信息交互过程进行了分析,建立了二者的业务集成框架模型,分析了ERP与MRO系统的数据结构转换过程,提出了二者数据集成模型。应用Web Services完成了ERP与MRO的系统集成开发,包括服务BOM集成、备品备件管理集成等。研究结果实现了制造和服务阶段关键产品数据信息的集成与反馈,打通了从制造到服务阶段的数据传递与集成,对进一步研究复杂产品生命周期管理的信息集成具有一定的借鉴意义。  相似文献   
3.
I develop a new class of closed‐form option pricing models that incorporate variance risk premium and symmetric or asymmetric double exponential jump diffusion. These models decompose the jump component into upward and downward jumps using two independent exponential distributions and thus capture the impact of good and bad news on asset returns and option prices. The empirical results show that the model with an asymmetric double exponential jump diffusion improves the fit on Shanghai Stock Exchange 50ETF returns and options and provides relatively better in‐ and out‐of‐sample pricing performance.  相似文献   
4.
This paper breaks new ground by revealing and conceptualizing the marketization of science as a process that transforms scientific discoveries and markets through a series of choreographed contestations: moments of valuation that occur when different social worlds collide. We follow a scientific discovery, from the moment it entered an incubator, to uncover how valuation practices and market devices enact and contest diverse social values (i.e., what is worth doing) to generate economic value (i.e., what is worth paying for) at the science‐market‐entrepreneurship nexus. In contrast with commercialization of science studies that focus on institutional arrangements, this study explicates the practices and devices used by multiple market actors to transform a scientific discovery into a marketable object. In so doing, we characterise choreographed contestations and the mechanisms through which they operate to explain how specific valuations are performed to work out innovative next steps that unfold the marketization of science.  相似文献   
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6.
Valuation ratios divide stock price by accounting metrics such as earnings, earnings growth, and book value. This study adapts the general valuation framework in Ohlson and Juettner-Nauroth (2005) and Ohlson (2005) to present a unified approach for developing valuation ratios based on fundamentals, referred to as fundamental valuation ratios. One starts with a valuation model that is driven by an accounting metric a and its abnormal growth, then divides the valuation model by a to get a fundamental valuation ratio. For any valuation ratio, one can find a corresponding fundamental valuation ratio, as long as the valuation model is based on the same metric a as the valuation ratio denominator.  相似文献   
7.
This paper investigates the bank-level responses of a bank-intermediated instrument of trade finance to a negative global liquidity shock in Korea. Using a factor-augmented vector autoregression approach, the results show that there exists significant heterogeneity in bank-level trade-finance responses to a global liquidity shock. In addition, we find that the source of the heterogeneity is the bank-level foreign currency liquidity condition; banks with a better foreign currency liquidity condition may dampen the negative impact of a global liquidity shock on trade-finance.  相似文献   
8.
This study back-tests a marginal cost of production model proposed to value the digital currency Bitcoin. Results from both conventional regression and vector autoregression (VAR) models show that the marginal cost of production plays an important role in explaining Bitcoin prices, challenging recent allegations that Bitcoins are essentially worthless. Even with markets pricing Bitcoin in the thousands of dollars each, the valuation model seems robust. The data show that a price bubble that began in the Fall of 2017 resolved itself in early 2018, converging with the marginal cost model. This suggests that while bubbles may appear in the Bitcoin market, prices will tend to this bound and not collapse to zero.  相似文献   
9.
资本市场认为互联网公司市值的驱动因素应包括盈利因子、运营因子、流量因子和协同因子。将协同效应指标考虑到公司估值体系中,意图构造互联网公司优化估值模型。使用美股上市的互联网企业数据建立了评价指标体系,通过因子分析实现了二级指标降维,通过实证分析确认了四个因子与公司市值的相关关系,最后构建了基于人工神经网络BP算法的互联网公司估值模型,通过预测数据的检验发现模型的准确度较高。随着2018年互联网公司美股上市潮的持续,该模型能有效为资本市场估值提供参考。  相似文献   
10.
Forest ecosystems deliver valuable services to humanity. However, many forests are being degraded and their services have been undervalued. The main problem lies in the inadequate institutional arrangements for forest governance. This paper aims to assess the effects of alternative forest governance arrangements on the provision and economic values of forest ecosystem services (FES) in Vietnam. The study presents a framework for mapping land use and land cover (LULC) change stemming from actual and hypothetical changes in forest governance regimes, quantifies the resulting changes in the provision of FES, and estimates the associated economic values. In the context of the study site in the North Western uplands of Vietnam, we test three alternative forest governance scenarios: business as usual, with a dominant government role; a community-based governance regime; and a private, individual-based forestry governance regime. Scenarios are based quite closely on the way these regimes are (or might be expected to be) implemented in Vietnam. For each forest governance scenario, we map LULC changes based on land suitability analysis and transition likelihood for the period 2010 − 2020. The resulting maps are used as inputs into the InVEST (Integrated Valuation of Environmental Services and Tradeoffs) model, which is used to estimate the quantity of three specific FES: carbon storage/sequestration, sediment yield, and water yield. We apply economic valuation methods to value these services: the social cost of carbon is used to estimate the economic values of carbon storage/sequestration; the cost of removing sediment deposited in reservoirs is applied for valuing the reduction of sediment yield, and the residual value of water supply for hydropower generation is used for valuing water yield. The results show that forest governance regimes have a significant effect not only on forest LULC, but also on the quantity and values of FES derived from forests. The FES are differentially affected by alternative forest governance regimes: some FES increase in quantity and value under some governance regimes and decrease under others. Of the three forest governance regimes examined, there is no one regime that will always be ‘better’ than the others in terms of provisioning all considered FES. For the specific context of Vietnam, we find that the private forest governance scenario is inferior to the community-based governance scenario, as an alternative to the current state-based governance. Because our results pertain to the scenarios as constructed, rather than generally to broad categories of governance regimes, there remains the possibility that regimes can be constructed that outperform all of those examined here.  相似文献   
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