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101.
Data envelopment analysis (DEA) has recently become relatively popular with road safety experts. Therefore, various decision-making units (DMUs), such as EU countries, have been assessed in terms of road safety performance (RSP). However, the DEA has been criticized because it evaluates DMUs based only on the concept of self-assessment, and, therefore does not provide a unique ranking for DMUs. Therefore, cross efficiency method (CEM) was developed to overcome this shortcoming. Peer-evaluations in addition to self-evaluation have made the CEM to be recognized as an effective method for ranking DMUs. The traditional CEM is based only on the standard CCR (Charnes, Cooper and Rhodes) model, and it evaluates DMUs according to their position relative to the best practice frontier while neglecting the worst practice frontier. However, the DMUs can also be assessed based on their position relative to the worst practice frontier. In this regard, the present study aims to provide a double-frontier CEM for assessing RSP by taking into account the best and worst frontiers simultaneously. For this purpose, the cross efficiency and cross anti-efficiency matrices are generated.Even though a weighted average method (WAM) is most frequently used for cross efficiency aggregation, the decision maker's (DM) preference structure may not be reflected. For this reason, the present study mainly focuses on the evidential reasoning approach (ERA), as a nonlinear aggregation method, rather than the linear WAM. Equal weights are often used for cross efficiency aggregation; consequently, the effect of the DM's subjective judgments in obtaining the overall efficiency is ignored. In this respect, the minimax entropy approach (MEA) and the maximum disparity approach (MMDA) are applied for determining the ordered weighted averaging (OWA) operator weights for cross efficiency aggregation. The weighted cross efficiencies and cross anti-efficiencies are then aggregated using the ERA. Finally, the proposed method, called DF-CEM-ERA, is used to evaluate the RSP of EU countries as well as Serbian police departments (PDs).  相似文献   
102.
Fire stations play a central role in protection and response activities as part of emergency management services in cases of fire incidences. With the rising urban populations and city expansions, the demand for more fire services resultantly increases. It then becomes critical to effectively plan the location of emergency facilities to adequately service the population and ensure the protection of lives and infrastructure. This study, therefore proposes the use of the fuzzy extension of the Multi-Criteria Decision-Making (MCDM) method of Analytical Hierarchical Process (AHP), hence called fuzzy AHP, integrated with Geographic Information Systems (GIS) approach to optimally site new fire stations for the case of Istanbul region. This proposed fuzzy approach simulates the subjective expert judgements for the preferences of the six criteria assessed for fire station suitability mapping and thereby accounted for the uncertainty of crisp comparison values via triangular fuzzy numbers (TFNs). The criteria weights evaluated from this procedure were used in a weighted overlay analysis of the reclassified criteria map layers in ArcGIS to generate a fire station suitability map. These resultant fuzzy AHP criteria weights were validated using another MCDM technique, called Best-Worst Method (BWM) and found to be comparable and consistent. The criteria that had the strongest influence on the selection of sites for fire stations were identified to be: the density of hazardous material facilities (DHM), a high population density (HPD) and proximity to main roads (PMR) with associated weights of 33.3%, 24.4% and 15.2%, respectively. Based on a thorough assessment within the areas represented by class values ranging from 3 to 5 on the suitability map, a total of 34 new fire station sites were selected complementing the existing 121 fire stations. Further, a prioritization analysis from low, medium to high, was performed to plan the phases for the construction of new fire stations in view of competing budgetary needs and resource constraints. The methodology to achieve this was proposed and modelled for enhancing the decision-making process in urban fire station site selection studies.  相似文献   
103.
当市场环境不好以及不确定性增加时,基金进行安全投资转移。企业积极履行社会责任所形成的声誉资本具有“类保险”作用,在面临负面事件或不确定性环境冲击时能够防止股价大幅下跌和市值损失;基金是否会在市场环境不好时将投资组合转向社会责任绩效更高的股票进行安全投资转移呢?使用2010—2017年开放式基金样本,实证检验了企业社会责任、市场环境与安全投资转移之间的关系。研究发现,在市场环境表现不佳时,基金避险需求增加,倾向将投资组合更多地转向社会责任绩效高的股票进行安全投资转移;进一步研究发现基金和基金经理特征影响基金的安全投资转移行为,净资金流入较少、历史业绩差、经理选股能力差的基金根据企业社会责任进行安全投资转移的程度大。研究还发现,基金的安全投资转移行为对基金业绩和基金收益波动产生了积极影响。  相似文献   
104.
This research examines whether social media (Twitter) happiness sentiment and country-level happiness sentiment indices predict cross-border ETF returns. To account for complicated associations between happiness sentiment and ETF returns, we use a quantile regression approach and find that Twitter and trading market (U.S.) happiness sentiments are strong predictors of future ETF returns, for which both have far greater predictive power than those of their home countries. Home country happiness indices exhibit asymmetric impacts across quantiles, suggesting the importance of trading country (U.S.) and Twitter happiness sentiments. Higher U.S. and home countries’ freedom to make life choices, absence of corruption perception, and confidence in national government precede higher ETF returns, while U.S. GDP, social support, health life expectancy, positive affect, and negative affect precede lower (abnormal) returns. We find that higher return quantile country ETFs provide a safe haven for U.S. investors during a U.S. bear market.  相似文献   
105.
This paper estimates the causal effect of fiscal rules on fiscal balances in a panel of 142 countries over the period 1985–2015. Our instrumental variable strategy exploits the geographical diffusion of fiscal rules across countries. The intuition is that reforms in neighboring countries may affect the adoption of domestic reforms through peer pressure and imitational effects. We find that the mere existence of fiscal rules correlates with lower deficits, but the positive link disappears when endogeneity is correctly addressed. However, when considering the strength of rules through a continuous index of fiscal rules’ design, we show that well-designed rules have a statistically significant impact on fiscal balances. We conduct several robustness tests and show that our results are generally robust and not affected by weak instrument problems.  相似文献   
106.
The impact of the economic crisis 2008-09 was remarkably different in the 12 “old” member states in the Euro-zone. Five of them were hit especially badly; four of them even had to be bailed out by the rest in one way or another. This paper asks if one could have foretold, based solely on information available prior to 1999, which of the countries then about to enter the Euro-zone would run into economic trouble once a serious economic crisis occurred. The focus is on the (post)predictive power of three kinds of leading indicators: economic indicators, political indicators (indicating quality of governance), and indicators derived from the theory of optimal currency areas (OCA). Since there are more indicators than cases, PLS-regression is used to gauge the (post)predictive strength of the indicators examined. The results show that political indicators have quite some (post)predictive power in this case, whereas indicators derived from OCA-theory do not do too well. Economic indicators perform better than indicators derived from OCA-theory, but generally less well than the political indicators. Thus, the experience from the latest economic crisis in the Euro-zone suggests that more emphasis should be placed on the quality of governance record of a country when deciding if it should be deemed fit to become a member.  相似文献   
107.
This paper contributes to the literature on the relationship between city size and firm productivity by focusing on agglomeration, selection (market competition), and sorting (presence of firms with diverse productivity) effects using Chinese firm-level data for 1998–2013. Contrary to the existing literature, our parametric regression estimates from nearly two million firms show that when the selection effect is controlled, productivity advantage in big cities is reversed. This outcome is explained through a quantile regression showing the existence of left-sided sorting (inefficient firms sort themselves to larger cities) in big cities which is not captured in existing empirical literature. We further find that (1) left-sided sorting is stronger in exporters than non-exporters; (2) is also generated mainly in enterprises with high asset-liability ratios; and (3) selection has a positive effect on firm productivity, suggesting that market competition is key in an explanation of the rapid growth of big cities in China.  相似文献   
108.
ABSTRACT

This paper analyses the role of user-supplier relationships in the innovation dynamics of the Oil and Gas (O&G) industry, from an analysis supported by R&D and patent application data. This paper points to some recent interesting phenomena in the O&G sector, such as: (i) the remarkable advancement of two Chinese oil companies; (ii) the significant growth in O&G companies’ technological engagement in exploration and production (E&P) from the 2000s; (iii) the non-negligible increase in the application of O&G companies’ patents for renewable energy. Moreover, by working with the oil and gas chain complete, we show that the performance of the companies oil and gas equipment and services industry (O&GES) is restricted to the upstream activities. Finally, we bring up some arguments that have as objective relativise the typology of R&D intensity adopted by OECD.  相似文献   
109.
基于引证关系,利用知识图谱、社会网络分析等方法,对1981—2019年《经济地理》创刊以来知识溢出的特征与变化规律进行分析。经济地理学研究的专业综合性、学科交叉性特点,在《经济地理》期刊知识溢出的特征与变化中得以充分诠释。期刊知识溢出的作用与变化,不仅体现在促进作者合作网络形成与机构合作关系的深化上,也体现在对城市化、区域经济发展、区域旅游发展等研究领域的推动作用与变化上。期刊知识溢出的特征与变化在其主题构成、作者贡献、机构力量与前沿引领等的探讨中进一步得以明确。具体地,城市化研究的知识溢出作用,从城市化和城镇化、土地利用、生态环境等方面,逐渐转向新型城镇化、城市网络、生态环境、协调发展等主题;区域经济发展研究的知识溢出作用,经历了从经济联系转向产业集群、再转向空间相互作用关系的主题变化;区域旅游发展研究的知识溢出作用,则从旅游资源、旅游业、生态旅游等方面,逐步转向乡村旅游、旅游经济与协调发展等主题。以国家战略与发展政策为主要导向,促进国内经济地理学的研究与发展,是《经济地理》期刊知识溢出的核心内容与集中反映。  相似文献   
110.
In this paper, we propose a goal-based investment model that is suitable for personalized wealth management. The model only requires a few intuitive inputs such as size of wealth, investment amount, and consumption goals from individual investors. In particular, a priority level can be assigned to each consumption goal and the model provides a holistic solution based on a sequential approach starting with the highest priority. This allows strict prioritization by maximizing the probability of achieving higher priority goals that are not affected by goals with lower priorities. Furthermore, the proposed model is formulated as a linear program that efficiently finds the optimal financial plan. With its simplicity, flexibility, and computational efficiency, the proposed goal-based investment model provides a new framework for automated investment management services.  相似文献   
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