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11.
The endo–exo problem lies at the heart of statistical identification in many fields of science, and is often plagued by spurious strong-and-long memory due to improper treatment of trends, shocks and shifts in the data. A class of models that has shown to be useful in discerning exogenous and endogenous activity is the Hawkes process. This class of point processes has enjoyed great recent popularity and rapid development within the quantitative finance literature, with particular focus on the study of market microstructure and high frequency price fluctuations. We show that there are important lessons from older fields like time series and econometrics that should also be applied in financial point process modelling. In particular, we emphasize the importance of appropriately treating trends and shocks for the identification of the strength and length of memory in the system. We exploit the powerful Expectation Maximization algorithm and objective statistical criteria (BIC) to select the flexibility of the deterministic background intensity. With these methods, we strongly reject the hypothesis that the considered financial markets are critical at univariate and bivariate microstructural levels.  相似文献   
12.
While innovation has become a pervasive term, many of today’s organizations still find innovation elusive. One reason may be that much of what is being said about innovation contributes to misunderstanding. To truly manifest innovation and reap its benefits, one must recognize that innovation is three different things: innovation is an outcome, innovation is a process, and innovation is a mindset. Innovation as an outcome emphasizes what output is sought, including product innovation, process innovation, marketing innovation, business model innovation, supply chain innovation, and organizational innovation. Innovation as a process attends to the way in which innovation should be organized so that outcomes can come to fruition; this includes an overall innovation process and a new product development process. Innovation as a mindset addresses the internalization of innovation by individual members of the organization where innovation is instilled and ingrained along with the creation of a supportive organizational culture that allows innovation to flourish. Such an understanding defines necessary elements, considerations, and vernacular surrounding the term so that better decisions can be made, thereby enabling innovation and having a greater propensity to succeed.  相似文献   
13.
河北省北部山区农村生态环境治理及绩效评价   总被引:1,自引:0,他引:1  
[目的]农村生态环境是一个复杂的系统,严重的生态环境问题制约着农村经济的发展以及新农村建设,探讨其治理和绩效,有利于解决生态环境建设中的各种问题,对于区域发展具有重要的理论和实践意义。[方法]文章通过构建农村生态环境治理及绩效评价指标体系,采用层次分析法确定各个指标的权重以及灰色关联法分析各指标间的灰色关联度。[结果]河北省北部山区农村生态环境治理绩效评价指标体系要素层中权重值大小依次为生态经济(0. 483 9)、生态环境(0. 273 6)、生态人居(0. 137 1)、生态保护(0. 105 4),说明该地区农村经济水平已达到一定水平,但生态环境、生态保护等仍有待提高。灰色关联法计算结果表明河北省北部山区生态环境中关联系数最高的是畜禽粪便处理率(0. 754),生态经济中关联系数最高的是农民人均纯收入(0. 624),生态保护中关联系数最高的是化肥施用量(0. 846),生态人居中关联系数最高的是饮用水合格率(0. 682),而关联度大小依次为生态保护(0. 724)、生态环境(0. 662)、生态人居(0. 573)、生态经济(0. 543),说明该地区生态环境治理仍有很大空间。[结论]研究结果指出河北省北部山区农村生态环境治理的不足,为进一步完善区域生态环境具有重要的指导意义。  相似文献   
14.
[目的]开展农业干旱危险性评价与区划研究,为辽宁省西北地区农业防旱抗灾工作提供科学依据。[方法]文章根据联合国国际减灾战略署(ISDR)对农业干旱危险性的定义,分析了构成研究区作物干旱危险性的致灾因子和孕灾环境因子,采用层次分析法确定了各因子的权重,构建了研究区农业干旱危险性评价指标和模型。以2009年为例,通过利用降雨、土壤、农业生产类型及地形等数据计算了辽西北地区农业干旱危险性评价指数,利用自然间断点法分级干旱危险性评价指数,并借助GIS技术,绘制研究区农业干旱危险性等级区划图。[结果] 2009年作物生长期间研究区农业干旱危险性由高到低排列为:朝阳市葫芦岛市锦州市阜新市铁岭市沈阳市。[结论]辽西北地区农业干旱危险性等级区的划分,能够帮助政府管理部门为面临干旱威胁不同的区域建立适当的防灾方法和有效的应急预案。  相似文献   
15.
The public sector plays an important role in the German “Energiewende”. Besides energy management in municipal properties the local government can also support the switch to renewable energy sources through a change in energy supply structures within in their region. Methods of Multi-Criteria Decision Making (MCDM) from Operations Research are helpful regarding that challenge, as they are able to assess the sustainability of local energy concepts, since they not only offer stakeholders the opportunity to participate, but also consider multiple conflicting criteria. In that way, the acceptance of local energy projects and the participation of stakeholders in the decision process are supported. The case study presented in this paper illustrates the results of a MCDM process employed to identify a sustainable bioenergy concept in a rural village in Lower Saxony, Germany. Our analysis revealed not only the opportunities and challenges associated with executing an MCDM process to support the realization of local bioenergy projects, but also discusses potential limitations of the methods.  相似文献   
16.
ABSTRACT

This paper aims to explore the conceptual potential of the Deleuzian notion of the encounter in order to better understand the genealogy of opportunities. We adopt a processual perspective of opportunities. In order to translate this notion to the domain of entrepreneurship, we analysed and interpreted Jean-Marc Vallée’s Dallas Buyers Club. This film follows the creation of the first club in the United States that illegally allowed HIV-positive people to supply themselves with foreign antiretroviral drugs from Mexico or Japan. The article highlights encounters in this process that disturb the entrepreneur’s belief systems and allow him or her to be open to potential opportunity. It finally explores how the encounter may improve our understanding of the political becoming of opportunities within the entrepreneurial process.  相似文献   
17.
Although over 40 jurisdictions have adopted a tax on sugar-sweetened beverages (SSBs) for public health worldwide, it is still debated in many places. Policy processes can influence the prospect of an SSB tax, its design and its public health benefits. To get an insight into such processes, we undertook a case study of the soda tax enacted in France on the 1st of January 2012. Newspaper articles (2003–2013) and institutional documents (2007–2012) were identified using keywords and search engines. Qualitative data extraction and analyses were performed on a thematic and chronological basis, with guidance from Kingdon’s multiple streams theory (MST). Triangulation was enhanced by using complementary sources. This study shows that in August 2011, the French government surprisingly announced a €3.58 cent/L excise tax on SSBs, excluding juices with no added sugars and non-calorically sweetened beverages (NCSBs). As part of a large budgetary plan, the proposal aimed to reduce SSB consumption and raise revenue that was earmarked for health care. Several conditions contributed to opening a policy window: The announcement occurred in the context of severe budgetary deficits; soda tax scenarios had already been discussed at a high level; and the bill was supported by convinced political leaders. Subsequently, the tax successfully passed through the legislative process due to a series of unexpected events, but its public health rationale and design were weakened. The first event was the disorganised reaction by the food industry, despite their sharp opposition to the tax. The next event was the support of the soda tax that came from a majority of Deputies, provided that the revenues would serve another purpose: relieving wage costs in the farming sector. Finally, policy entrepreneurs favoured a compromise to make the tax politically acceptable and legally viable: The tax rate doubled, the scope was extended to NCSBs and revenues were split between health care and agriculture. This study sheds light on influence factors that could be taken into account by public health actors willing to influence soda tax policy processes.  相似文献   
18.
[目的]通过测算各地区农业科技资源的配置能力,分析其比较优势并找出不足以便弥补差距,促进各区域农业科技配置能力的提高,为各地区农业经济的发展提供支持。省级农业科学院作为各省市规模最大、综合实力最强的农业科研机构,是农业科技创新的重要主体之一,分析其科技资源配置能力具有重要的现实意义。[方法]基于2009—2016年相关数据,遴选了有代表性的评价指标体系,运用突变级数法计算农业科技资源配置能力,运用NRCA模型定量分析农业科技资源配置效益的比较优势。[结果]山东农业科学院科技资源配置能力位居全国第一,甘肃、江苏、青海农业科学院分别在农业科技人力、物力、财力资源方面具有明显的比较优势。[结论]省级农业科学院科技资源配置能力区域差异十分明显,但区域格局变化不大,且大致与各地区经济实力相吻合;农业科技资源配置能力较高的农业科学院大多在农业科技物力资源配置效益方面具有比较优势,在农业科技人力、财力资源配置效益方面不具备比较优势。  相似文献   
19.
With the expansion of urbanization caused by the growth of population and industrial activities, the urban/city and suburban areas are facing a variety of environmental threats. Although more research and urban policy has advocated and practiced the development of green infrastructure (GI) to support urban sustainable environment, the evaluation framework for the development of GI for promoting environmental sustainability is still insufficient. Moreover, the Analytic Hierarchy Process (AHP) commonly applied in published literature, makes an unrealistic assumption of independent relationships among dimensions/criteria in decision making for satisfying the real-world problem. Therefore, the purpose of this study is to construct the evaluation framework, including four dimensions and related ten criteria, using a new hybrid-modified multiple attribute decision-making (MADM) model for developing and improving the GI for promoting environmental sustainability. This MADM model is combined with three different methodologies of MADM, including the Decision-Making Trial and Evaluation Laboratory (DEMATEL) for constructing the influential network relation map (INRM) to explore the complex influential inter-relationships and DEMATEL based on Analytic Network Process (DANP) for determining the influential weights with the VIse Kriterijumska Optimizacija I Kompromisno Resenje (VIKOR) for evaluating and presenting improvement strategies for six different GIs. The empirical study indicates that DEMATEL and DANP Results suggest that decision-makers should pay more attention to the improvement of Design (D4) and Materials (D2) in terms of dimensions when utilizing the GI to promote environmental sustainability. Because these dimensions are enhanced, Species (D1) and Energy (D3) will be improved in synchronization. From the perspective of criteria, five are key core criteria and need to be focused on first: increasing the green coverage rate (B9), utilizing sustainable materials (B4), using ecological engineering (B8), shaping species biodiversity (B1), and reducing energy consumption (B5). Modified VIKOR reveals that “grass swales” are a comparatively better choice among six GIs for promoting environmental sustainability toward achieving the aspiration level. Therefore, this MADM model is beneficial to provide a more convincing assessment framework and improvement strategies for the development of GI for promoting environmental sustainability. As a result, these modified MADM models can be shown more conveniently and reasonably than traditional methods such as traditional AHP or ANP method.  相似文献   
20.
This study examines the effect of key internationalization contingencies on SME survival. We argue early internationalization increases the probability of firm failure, while international experience reduces it. However, the survival odds among international new ventures may be improved by their post-entry international expansion scope and speed, and by managers’ competencies. These internationalization facets provide firms with opportunities to develop and exploit their resources and capabilities, and thus enhance their survival chances. Drawing on a sample of 271 manufacturers followed between 2005 and 2014, we find results that provide support to most of our arguments, and hold theoretical and managerial relevance.  相似文献   
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