Foreign Direct Investment and the External Wealth of Nations: How Important Is Valuation?

While the balance sheet approach has increased the focus on position data, differences in valuation practices for foreign direct investment (FDI) make cross‐country comparisons difficult. To enhance comparability, the IMF's Balance of Payments and International Investment Position Manual, sixth edition, which some countries have already implemented and others will implement in the coming years, recommends seven methods for valuation of unlisted FDI. This paper demonstrates that both the valuation method and simple differences in estimation techniques can fundamentally change a country's financial balance sheet. Using Denmark as an illustration, unlisted FDI equity liabilities vary from 22 to 156 percent of GDP when applying different estimation techniques, but just one valuation method, price to earnings. These measurement uncertainties can lead to important misunderstandings and affect policy recommendations, thus pointing to the need for further international harmonization. While the results are presented in an FDI context, the uncertainties also apply to other macroeconomic datasets, including national accounts statistics.     

基于统计可信度的压缩感知协作频谱检测算法

压缩感知为认知无线电的宽频谱感知提供了一种新的方法和思路。基于压缩感知的原理,提出了一种多认知用户协作场景下基于用户统计可信度的协作频谱检测算法。该算法使用正交匹配协作追踪算法获得认知区域内的频谱占用情况,根据不同认知用户频谱检测的历史准确度综合判定用户感知结果的统计可信度。仿真结果表明,该算法在不同用户数、不同采样值、不同信噪比变化范围下其检测性能均优于传统算术平均方法,有效改善了检测性能。     

改进的“当前”统计模型变采样率目标跟踪算法

为满足实际雷达系统对高精度和高实时性的要求,提出了一种改进的“当前”统计模型变采样率机动目标跟踪算法。该算法针对“当前”统计模型必须预设加速度极值和机动频率的问题,提出一种加速度方差和机动频率在线同步自适应方法,建立改进的“当前”统计模型机动目标跟踪算法;针对在线自适应方法计算量大的问题,结合采样周期的大小与目标机动特性的关系,引入变采样率方法。仿真结果表明,与传统“当前”统计模型相比,改进的“当前”统计模型机动目标跟踪算法能显著提高对不同机动强度目标的跟踪精度;变采样率方法通过减少采样点数,节省了系统资源,提高了跟踪实时性;所提算法将两者结合,用传统的“当前”统计模型1.5～2倍的平均采样周期得到了更小的位置均方根误差,实现了用单模型方法同时改善跟踪精度和实时性的目的。     

政府监管对共享单车发展的影响——基于出行大数据的挖掘与分析

共享单车作为一种环保便捷的智能交通工具,由于过量投放、无序占道和运维错配等突出问题,严重影响公共秩序,政府监管势在必行。然而,政府严格监管对共享单车发展有何影响,一直在理论研究和社会实践中存在诸多争议。基于此,通过对成都中心区摩拜单车用户出行数据进行挖掘和分析,从政府、出行者和运营商视角,评估现行政府监管实施效果。研究表明,政府监管后,尽管出行意愿受到一定程度抑制,运维难度加大,但共享单车的公共属性得以强化,共享单车行业竞争格局得以调整,将有利于共享单车发展潜力的释放。     

工业企业提高能源统计数据质量的方法浅析

在当前的国民经济核算中,能源统计是非常重要的组成部分,能源统计数据的质量将直接影响对我国国民经济的核算,对制定宏观调控政策及相关的能源政策都会产生不同程度的影响。所以,针对我国的能源统计工作需要不断强化落实并完善有关的管理办法。论文在介绍加强能源统计管理的重要性的基础上,分析了工业企业能源统计管理的成效和问题,提出了提升工业企业能源统计数据质量的方法,以期提升能源统计工作的质量。     

A measure of regional influence with the analytic network process

The metropolitan region is commonly defined by a socio-spatial network of urban nodes that are linked in territory and function. Such a network is differentiated by size and dominance of the linked nodes, characterized by physical or virtual flows of a wide-ranging variety. The analytic network process (ANP) is a multi-criteria analytic method that measures the influence or dominance of the nodes in a network with feedback. We illustrate how ANP determines county rank as a measure of influence in a metropolitan statistical area (MSA) defined by its interrelated socio-economic and spatial elements qualitatively and quantitatively. We compare the ANP results to similar measures of regional influence in the literature.     

Estimation bias in choice models with last choice feedback

The study compares two estimation methods for choice models with last choice feedback, using simulated and real data. The first method ignores the impact of unobserved heterogeneity on observed choices via presample choices, while the second method approximates this impact by a stochastic relationship. In panels with less than 10 choices per panelist, the first method overstates the impact of last choice on current choice and understates the impact of intrinsic preferences (i.e., brand intercepts). The second method performs significantly better than the first method. Under both methods, an increase in the number of heterogeneous coefficients in the model tends to increase the bias in the estimates. The largest bias occurs when lagged choice coefficients are heterogeneous.     

遥感技术农业资源台账建设应用潜力分析

[目的]为了系统地分析遥感技术在农业资源台账建设中的应用潜力。[方法]文章通过文献研究,阐述了农业资源台账的研究现状,分析了农业资源遥感监测数据源与监测技术的发展趋势,研判了当前遥感技术在农业资源台账建设中的应用潜力。[结果]（1）农业资源台账的建设内容主要包括农业资源清单、农业资源评价两个方面,具有空间与时间两种属性。（2）农业遥感数据源向着高空间分辨率、高时间分辨率、高光谱分辨率的方向发展,其监测技术向着多源遥感数据融合应用、智能分类、多维海量数据高效计算的方向发展。（3）遥感技术可对农业资源清单中的主要农业自然资源和社会经济资源的信息进行获取,对农业资源组分评价与农业生态系统整体评价也有很大潜力。[结论]总的来看,农业资源台账建设内容不断丰富,遥感技术在农业资源台账建设中的应用能力显著提升,其应用潜力仍有很大的上升空间,对高效开展农业资源台账建设具有积极作用。     

1990年以来江苏省区域经济差异时空格局演化及其成因分析

以1990—2007年江苏省县域人均GDP为研究指标,运用不平衡指数和空间统计模型对江苏省区域经济发展水平进行定量研究,并结合GIS的空间分析功能,系统分析了江苏省区域经济发展时空差异及空间格局演化。结果表明:江苏省区域经济发展在空间上具有较强的自相关性,在整体格局上呈现出一定的集聚态势,空间格局更多表现为苏南部分地区的高度集聚和苏北部分地区的集聚态势,成为江苏省区域经济发展的集聚核心区和低度集聚区,而苏中地区的集聚态势显得并不强烈。同时,针对区域经济自相关性发展趋势进行解释并指出以县域经济为单元的区域经济发展空间差异将长期存在。最后,构建空间数据模型对此种格局形成的原因进行空间统计学上的探讨,指出规模企业空间分布差异及人才空间分布差异是导致县域经济发展差异的主要因素,为区域经济差异分析提供了一种交互式的、可视化的新手段,进而为政府部门制定区域经济协调发展政策提供决策依据。     

Beyond Bitcoin: What blockchain and distributed ledger technologies mean for firms

Blockchain technologies are benefiting from significant interest in both societal and business contexts. Cryptocurrencies like Bitcoin have grown rapidly in user adoption over the past 8 years. However, blockchain technologies, which fuel cryptocurrencies, have the potential to extend to other business applications even more profoundly. Blockchain can be leveraged to drive innovation and increase efficiencies in new domains—including digital arts management, supply chains, and healthcare—but there remain technical, organizational, and regulatory headwinds that must be overcome before mass adoption can occur. In this article, we provide a brief history of blockchain and identify some of the key features that have enabled its popular uptake in the world of cryptocurrencies. We discuss how blockchain technologies have evolved from traditional software and web technologies and then examine their underlying strengths and evaluate new, noncryptocurrency use cases. We conclude with a look at the limitations of blockchain and present several important factors for managers considering blockchain implementation within their organizations.