Convex risk measures for the aggregation of multiple information sources and applications in insurance

We propose a novel class of convex risk measures, based on the concept of the Fréchet mean, designed in order to handle uncertainty which arises from multiple information sources regarding the risk factors of interest. The proposed risk measures robustly characterize the exposure of the firm, by filtering out appropriately the partial information available in individual sources into an aggregate model for the risk factors of interest. Importantly, the proposed risks can be expressed in closed analytic forms allowing for interesting qualitative interpretations as well as comparative statics and thus facilitate their use in the everyday risk management process of the insurance firms. The potential use of the proposed risk measures in insurance is illustrated by two concrete applications, capital risk allocation and premia calculation under uncertainty.     

The Role of Inflation Target Adjustment in Stabilization Policy

How and under what circumstances can adjusting the inflation target serve as a stabilization-policy tool and contribute to welfare improvement? We answer these questions quantitatively with a standard New Keynesian model that includes cost-push-type shocks. Our proposed inflation target rule calls for the target to be adjusted in a persistent manner and in the opposite direction to the realization of a cost-push shock, which is essentially a makeup strategy. The inflation target rule, combined with a Taylor-type rule, significantly reduces inflation fluctuations originating from cost-push shocks and mitigates the stabilization trade-off, resulting in a similar level of welfare to that associated with the Ramsey optimal policy.     

The puzzle of greenhouse gas footprints of oil abundance

The present inquiry lays a groundwork for the analysis of the net greenhouse gas (GHG) footprint of oil in the oil-abundant settings. To address the research question, the study puts forward a three-sector decision model, which provides a common ground for the assessment of the interaction of the structuralist and institutional factors influencing environmental pollution in the oil-reliant economies. The study shows that fossil-fuel abundance triggers forces, which induce diametrically opposed effects concerning atmospheric pollution. These are the rising carbon-intensive oil extraction and processing and fossil-fueled power generation versus shrinkage of the carbon-intensive manufacturing and growth of the low-carbon tertiarization. The theoretical analysis enables compartmentalization of the essential factors, which determine GHG emissions in the respective countries. To assess the significance of the proposed theoretical framework, the study employs multivariate panel co-integration techniques and two-stage fixed effects estimations for a dataset of 38 oil-producing countries for the time period between 1960 and 2018. In contrast to the existing literature, this study drives apart from the black box approaches that employ just one omnibus variable, per capita income.     

Estimating yield curves of the U.S. Treasury securities: An interpolation approach

Following the approach of interpolation, this paper proposes the multiple exponential decay model to fit yield curves for both the U.S. TIPS market and the conventional Treasury security market. Several estimation methods, including the unconstrained/constrained nonlinear minimization, quadratic programming, and the iterative linear least squares, are applied to estimate the unknown parameters according to different curve‐fitting purposes. Comparisons between the proposed model and the alternatives show that the multiple exponential decay successfully (1) adapts to a variety of shapes associated with yield curves, (2) (partially) keeps in line with the economic interpretations of Nelson–Siegel summarized by Diebold and Li ( 2006 ), and (3) dominates the competing models in curve‐fitting performance measured by mean fitted‐price errors over the sample period. In addition, the exact specification of a nonparametric interpolation model is pinned down by applying three statistical tools, which enable us to jointly take into account validity, optimality, and parsimoniousness of the proposed model.     

Seven Fallacies Concerning Milton Friedman's “The Role of Monetary Policy”

This paper analyzes Milton Friedman's (1968a) article “The Role of Monetary Policy,” via a discussion of seven fallacies concerning the article. These fallacies are as follows: (i) “The Role of Monetary Policy” was Friedman's first public statement of the natural rate hypothesis. (ii) The Friedman–Phelps Phillips curve was already present in Samuelson and Solow's (1960) analysis. (iii) Friedman's specification of the Phillips curve was based on perfect competition and no nominal rigidities. (iv) Friedman's (1968a) account of monetary policy in the Great Depression contradicted the Monetary History’s version. (v) Friedman (1968a) stated that a monetary expansion will keep the unemployment rate and the real interest rate below their natural rates for two decades. (vi) The zero lower bound on nominal interest rates invalidates the natural rate hypothesis. (vii) Friedman's (1968a) treatment of an interest-rate peg was refuted by the rational expectations revolution. The discussion lays out the reasons why each of these seven items is a fallacy and infers key aspects of the framework underlying Friedman's (1968a) analysis.     

乌鲁木齐市建设用地对经济增长的贡献及Logistic曲线极限点估计研究

[目的]为提高乌鲁木齐市各生产要素的利用效率,明确经济发展模式,同时也为促进土地资源节约集约利用提供科学依据。[方法]基于C-D生产函数,以2005—2015年乌鲁木齐市统计数据为样本,借助EViews6.0和SPSS20.0软件测算出建设用地对经济增长的贡献率以及Logistic曲线极限点。[结果](1)资本投入要素对经济增长的贡献率(56.72%)最大,建设用地投入要素贡献(32.81%)次之,然后是劳动力投入要素贡献(13.25%),技术进步投入要素贡献(-2.78%)最小,但拥有很大的挖掘空间;(2)建设用地对经济增长的Logistic曲线极限点位于第二、三产业产值为1 522亿元处,对应2011年产值,2005—2011年建设用地对经济增长的贡献呈递增趋势,2011年之后贡献速度呈递减趋势,逐渐趋于平缓。[结论]建设用地对经济增长的驱动作用是有限的,只有通过技术创新才能实现经济发展模式由"依资本型"向"技术驱动型"转变。     

Can Poverty be Alleviated in China?

The 2000s witnessed the third poverty alleviation wave in China. Compared with its predecessors, the third wave distinguished itself by new interventions and redefined standards for the National Poor Counties. This paper evaluates the effectiveness of the new program using a data set consisting of 1,411 of China's western and central counties from 2000 to 2010. It combines the propensity score matching method with the difference‐in‐differences approach, which helps to avoid selection bias and track the policy impact on variables of interest at each time point. It is found that the non‐western local governments tended to manipulate data on income and output growth to maintain the special transfer payments disbursed exclusively to the National Poor Counties. It is also shown that the program failed to improve the infrastructure and sanitary conditions in general.     

技术生命周期视域下领域介入方向与时机研究——以图像处理技术领域为例

从专利文献数据出发，以Logistic曲线模型为研究方法，实证分析图像处理领域的整体技术发展及分支技术生命周期进程。研究发现，图像分割、图像识别技术方向及生物识别应用领域处于成长期，图像增强、图像去噪、图像重建、图像融合技术方向处于技术成熟期，而图像复原、图像编码技术及通信、医疗、交通、工业及遥感应用领域已经进入技术饱和期。结合图像处理领域分支技术方向及技术生命周期进展，可为相关创新主体介入领域的方向及时机提供参考信息。     

无穷范数松弛的低复杂度超奈奎斯特检测

超奈奎斯特(Faster-than-Nyquist,FTN)速率传输可以有效提高频谱效率，但这种非正交传输方式引入的严重码间串扰相应提高了接收端的处理难度。针对该问题，设计了一种基于循环成块传输的低复杂度检测算法。最优检测被建模为无约束的二元二次规划(Boolean Quadratic Program,BQP)问题，为了求解该NP-hard问题，采用无穷范数约束松弛原问题的非凸可行解集，并基于次梯度下降法提出松弛问题的有效优化算法。数值仿真结果表明，所提算法在误比特率(Bit Error Rate,BER)性能上优于频域均衡，且在可接受的性能损失范围内算法执行效率远高于理论最优的最大似然序列估计(Maximum Likelihood Sequence Estimation,MLSE)。     

Examining the change in wellbeing following a holiday

Building on existing evidence that tourism contributes to wellbeing, this study aims to investigate how both hedonic and eudaimonic wellbeing changes after a holiday. A longitudinal inquiry involving three waves of observation (during, the fourth week, and the eighth week following a holiday) was carried out in five tourism cities in China, using Latent Growth Curve models to analyze change. Results suggest that life satisfaction – an indicator of hedonic wellbeing – does not decline as expected whereas other indicators of hedonic wellbeing declined dramatically in the first month and then mildly in the second month following a holiday. Comparatively, eudaimonic wellbeing declined gradually and mildly during the same two-month intervals. Higher levels of optimal tourism experiences predicted slower declines of both hedonic and eudaimonic wellbeing. Theoretical, methodological, and practical implications are discussed.