“Relative Importance of Risk Sources in Insurance Systems”, Edward W. Frees,April 1998

Abstract

This paper considers a Sparre Andersen collective risk model in which the distribution of the interclaim time is that of a sum of n independent exponential random variables; thus, the Erlang(n) model is a special case. The analysis is focused on the function φ(u), the expected discounted penalty at ruin, with u being the initial surplus. The penalty may depend on the deficit at ruin and possibly also on the surplus immediately before ruin. It is shown that the function φ(u) satisfies a certain integro-differential equation and that this equation can be solved in terms of Laplace transforms, extending a result found in Lin (2003). As a consequence, a closed-form expression is obtained for the discounted joint probability density of the deficit at ruin and the surplus just before ruin, if the initial surplus is zero. For this formula and other results, the roots of Lundberg’s fundamental equation in the right half of the complex plane play a central role. Also, it is shown that φ(u) satisfies Li’s (2003) renewal equation. Under the assumption that the penalty depends only on the deficit at ruin and that the individual claim amount density is a combination of exponential densities, a closed-form expression for φ(u) is derived. In this context, known results of the Cauchy matrix are useful. Surprisingly, certain results are best expressed in terms of divided differences, a topic deleted from the actuarial examinations at the end of last century.     

Local banking and local economic growth in Italy: some panel evidence

This article provides new evidence on the contribution of local banking to local economic growth (i.e. at county level – the Italian ‘province’) in Italy. A comprehensive data set is used, which includes control variables for social capital and human capital as well as indicators of the quality of local infrastructures and the production structure of the local economy. A linear within-estimator technique with fixed effects is applied to a modified version of the so-called Barro regression in order to address the well-known econometric issues of reverse causality and estimation bias resulting from unobserved district-specific influences.     

Dynamic no-good-deal pricing measures and extension theorems for linear operators on L ∞

In an L ^∞-framework, we present majorant-preserving and sandwich-preserving extension theorems for linear operators. These results are then applied to price systems derived by a reasonable restriction of the class of applicable equivalent martingale measures. Our results prove the existence of a no-good-deal pricing measure for price systems consistent with bounds on the Sharpe ratio. We treat both discrete- and continuous-time market models. Within this study we present definitions of no-good-deal pricing measures that are equivalent to the existing ones and extend them to discrete-time models. We introduce the corresponding version of dynamic no-good-deal pricing measures in the continuous-time setting.     

OUTPUT FLUCTUATIONS PERSISTENCE: DO CYCLICAL SHOCKS MATTER?

The aim of this paper is to identify the different sources of persistence of output fluctuations. We propose an unobserved components model that allows us to decompose GDP series into a trend component and a cyclical component. We let the drift of the trend component switch between different regimes according to a first‐order Markov process. To calculate an appropriate p‐value for a test of linearity we propose a bootstrap procedure, which allows for general forms of heteroscedasticity. The performance of the bootstrap is checked by means of a Monte Carlo simulation. Our study concerns the USA. We find that cyclical shocks appear to play an important role on the observed persistence of output.     

Old Wine in New Bottles: Patenting Propensity

Journal of Industry, Competition and Trade - Although patenting propensity has been an old topic, our understanding of it is still fragmentary due to the complexity in the decision-making and the...     

相关行业上市公司政府补助对铁路公益性补贴的启示

针对航空运输、电信、石油等国家基础设施行业,通过分析这些行业上市公司的政府补助情况,在借鉴相关行业政府补助实践的基础上,提出建立铁路公益性运输发展基金,由中央政府和地方政府共同承担铁路公益性补贴责任的政策建议,同时认为铁路运输企业除争取公益性补贴外,还应争取税收优惠、专项补贴等其他补贴政策。     

WIC Participation and Relative Quality of Household Food Purchases: Evidence from FoodAPS

We examine the effect of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) on the quality of household food purchases using the National Household Food Acquisition and Purchase Survey (FoodAPS) and propensity score matching. A healthy purchasing index (HPI) is used to measure nutritional quality of household food purchases. WIC foods explain the improvement in quality of food purchases, not self‐selection of more nutrition‐conscious households into the program. The improvement in purchase quality was driven entirely by WIC participating households who redeemed WIC foods during the interview week. There was no significant difference between WIC participants who did not redeem WIC foods and eligible nonparticipants. In this sample, there is no evidence that lack of access to clinics has adverse effects on participation nor is there evidence that HPI depends on supermarket access. A supervised machine learning process supports our main conclusion on the importance of WIC foods.     

跨文化交际对应用型本科英语口语教学的影响

跨文化交际是指不同文化背景的人们之间的交际.外语教学的根本目的是实现跨文化交际,因此,应重视跨文化交际在口语能力教育上的重要作用,使学生了解语言与文化之间的关系,注重培养跨文化的意识,熟知中外文化异同与语言表达的形式特点,避免交际中出现语法应用正确却产生文化冲突的现象.     

考虑现实约束的不确定投资组合研究

作为实现财富增值保值的有效手段,投资组合引起了实务界和学术界的广泛关注。然而,以往研究大多忽略了金融市场的复杂性、外部因素的不确定性和历史数据的缺失性。为更准确刻画金融市场的现实状况、求解最优投资组合,本文引入不确定变量来描述证券收益率,进而构建包含交易成本、整手交易、流动性风险、交易上下限和行业分散化等现实约束的证券不确定投资组合模型;同时采用遗传算法进行计算,并代入模拟交易数据对比有现实约束和无现实约束投资组合模型的最优解。研究结果表明,引入现实约束条件后,最优投资组合发生了变化,期望收益率显著下降。上述研究结论带来的启示:对于证券投资者而言,在进行投资交易时,应充分考虑交易成本和不确定性风险,确保将投资风险限制在可控的范围之内;对于证券监管机构而言,应加强对证券市场的监督与管理,尤其是系统重要性机构,防范和化解流动性风险和不确定性风险。