Are There Differences in the Health– Socio‐economic Status Relationship over the Life Cycle? Evidence from Germany

Abstract. Most research on the relationship between health and socio‐economic status (SES) controls for age or investigates the relationship for a particular age range. This paper, however, examines the effect of SES on health across different age groups. Using data from the German Socio‐Economic Panel and controlling for health–SES endogeneity, we find that the health–income relationship does vary across the life cycle and between genders and different labor force status, with the impact of income on health relatively more pronounced for younger cohorts. The unemployed also have lower levels of health at all levels of income.     

Potential Pitfalls for the Purchasing‐Power‐Parity Puzzle? Sampling and Specification Biases in Mean‐Reversion Tests of the Law of One Price

The PPP puzzle is based on empirical evidence that international price differences for individual goods (LOOP) or baskets of goods (PPP) appear highly persistent or even nonstationary. The present consensus is these price differences have a half‐life that is of the order of five years at best, and infinity at worst. This seems unreasonable in a world where transportation and transaction costs appear so low as to encourage arbitrage and the convergence of price gaps over much shorter horizons, typically days or weeks. However, current empirics rely on a particular choice of methodology, involving (i) relatively low‐frequency monthly, quarterly, or annual data, and (ii) a linear model specification. In fact, these methodological choices are not innocent, and they can be shown to bias analysis towards findings of slow convergence and a random walk. Intuitively, if we suspect that the actual adjustment horizon is of the order of days, then monthly and annual data cannot be expected to reveal it. If we suspect arbitrage costs are high enough to produce a substantial “band of inaction,” then a linear model will fail to support convergence if the process spends considerable time random‐walking in that band. Thus, when testing for PPP or LOOP, model specification and data sampling should not proceed without consideration of the actual institutional context and logistical framework of markets.     

Do Chief Executives’ Traits Affect the Financial Performance of Risk‐trading Firms? Evidence from the UK Insurance Industry

We examine the effects of four key dimensions of Chief Executive Officers’ (CEOs’) traits on six financial performance metrics using panel data for 1999?2012 drawn from the UK's property?casualty insurance industry. We find that CEO insurance experience and CEO financial expertise enhance financial performance, while two other CEO traits ? power and age ? are generally not significant. Our results thus reinforce the importance of CEO insurance industry expertise and CEO financial expertise in the management and trading of risks. Our results have potential commercial and policy implications.     

On the online multi-agent O–D <Emphasis Type="Italic">k</Emphasis>-Canadian Traveler Problem

In this article, we present new results on the online multi-agent O–D k-Canadian Traveler Problem, in which there are multiple agents and an input graph with a given source node O and a destination node D together with edge costs such that at most k edges are blocked. The blocked edges are not known a priori and are not recoverable. All of the agents are initially located at O. The objective is to find an online strategy such that at least one of the agents finds a route from the initial location O to a given destination D with minimum total cost. We focus on the case where communication among the agents is limited in the sense that some travelers can both send and receive information while the others can only receive information. We formalize the definition of agents’ intelligence by specifying three levels. We introduce two online strategies which utilize higher levels of agents’ intelligence to provide updated lower bounds to this problem. We show that one of our strategies is optimal in both cases with complete and limited communication in the special case of O–D edge-disjoint graphs and highest level of agents’ intelligence.     

Design of the Reverse Channel for Remanufacturing: Must Profit‐Maximization Harm the Environment?

A key attribute of a remanufacturing strategy is the division of labor in the reverse channel, especially whether remanufacturing is performed in‐house or outsourced. We investigate this decision for a retailer who accepts returns of a remanufacturable product. Our formulation considers the cost structures of the two strategies, uncertainty in the input quality of the collected/returned used products, consumer willingness‐to‐pay for remanufactured product, the extent to which the remanufactured product cannibalizes demand for a new product, and the power structure in the channel. For the profit‐maximizing retailer, the differentials in variable remanufacturing costs drive strategy choice, and higher fixed costs of in‐house remanufacturing favors outsourcing. The variable remanufacturing costs and the balance of power in the prospective outsourced reverse channel are the key drivers of environmental impact, as measured by the retailer's propensity to remanufacture. While profitability and environmental goals often conflict, they align under certain conditions. These include (a) the third party has less bargaining power; or (b) the fixed cost for in‐house remanufacturing is relatively high. All else equal, when remanufacturing is outsourced, the environment fares better if the third party has leadership power. We generalize to the cases when remanufacturing achieves a quality level less than “good‐as‐new" and when used items have non‐zero salvage value. Analysis of these extensions illuminates how relative power in the reverse channel drives the firms’ preferences, as well as the end customers’ consumption experience.     

What Explains the 2007–2009 Drop in Employment?

We show that deterioration in household balance sheets, or the housing net worth channel, played a significant role in the sharp decline in U.S. employment between 2007 and 2009. Counties with a larger decline in housing net worth experience a larger decline in non‐tradable employment. This result is not driven by industry‐specific supply‐side shocks, exposure to the construction sector, policy‐induced business uncertainty, or contemporaneous credit supply tightening. We find little evidence of labor market adjustment in response to the housing net worth shock. There is no significant expansion of the tradable sector in counties with the largest decline in housing net worth. Further, there is little evidence of wage adjustment within or emigration out of the hardest hit counties.     

Does Experience Teach? Professionals and Minimax Play in the Lab

Does expertise in strategic behavior obtained in the field transfer to the abstract setting of the laboratory? Palacios‐Huerta and Volij (2008) argued that the behavior of professional soccer players in mixed‐strategy games conforms closely to minimax play, while the behavior of students (who are presumably novices in strategic situations requiring unpredictability) does not. We reexamine their data, showing that the play of professionals is inconsistent with the minimax hypothesis in several respects: (i) professionals follow nonstationary mixtures, with action frequencies that are negatively correlated between the first and the second half of the experiment, (ii) professionals tend to switch between under‐ and overplaying an action relative to its equilibrium frequency, and (iii) the distribution of action frequencies across professionals is far from the distribution implied by minimax. In each respect, the behavior of students conforms more closely to the minimax hypothesis.     

有感于“以&#215;&#215;落实&#215;&#215;”

一看“以&#215;&#215;落实&#215;&#215;”,也许会让人丈二和尚摸不着头脑,其实十分简单,有例为证——     

A primal–dual online algorithm for the <Emphasis Type="Italic">k</Emphasis>-server problem on weighted HSTs

In this paper, we show that there is a \(\frac{5}{2}\ell \cdot \ln (1+k)\)-competitive randomized algorithm for the k-sever problem on weighted Hierarchically Separated Trees (HSTs) with depth \(\ell \) when \(n=k+1\) where n is the number of points in the metric space, which improved previous best competitive ratio \(12 \ell \ln (1+4\ell (1+k))\) by Bansal et al. (FOCS, pp 267–276, 2011).     

On the <Emphasis Type="Italic">L</Emphasis>(2, 1)-labeling conjecture for brick product graphs

Let \(G=(V, E)\) be a graph. Denote \(d_G(u, v)\) the distance between two vertices u and v in G. An L(2, 1)-labeling of G is a function \(f: V \rightarrow \{0,1,\ldots \}\) such that for any two vertices u and v, \(|f(u)-f(v)| \ge 2\) if \(d_G(u, v) = 1\) and \(|f(u)-f(v)| \ge 1\) if \(d_G(u, v) = 2\). The span of f is the difference between the largest and the smallest number in f(V). The \(\lambda \)-number \(\lambda (G)\) of G is the minimum span over all L(2, 1)-labelings of G. In this paper, we conclude that the \(\lambda \)-number of each brick product graph is 5 or 6, which confirms Conjecture 6.1 stated in Li et al. (J Comb Optim 25:716–736, 2013).     

Unions’ and Firms’ Attitudes Towards Research Joint Ventures: When Will the Incentives Be Aligned?

Abstract. This paper studies the relationship between unionization and innovation activity. Under a unionized labour market, we find that when R&D spillovers are relatively low (high), cooperative, as well as non‐cooperative R&D is a strategic substitute (complement). Furthermore, irrespective of the spillover rate, cooperation increases firms’ profits, whereas it increases union utility only if spillovers are sufficiently high. Alignment of incentives between firms and unions requires that firms pay transfers in the form of ‘rent‐sharing’ to make a Research Joint Venture attractive to unions. Our results suggest that if spillovers are low enough, the amount of money that firms give up in order to buy unions’ acquiescence weakens their incentives to form a Research Joint Venture.     

从&#183;速&#183;处&#183;理

“总书记是百姓的贴心人” 2000年2月19日，新千年第一个元宵节的下午，一辆中巴车穿过广东茂名高州市漫山遍野的荔枝林，停在了高州市根子镇这座小山上的观荔亭旁。     

补锅&#183;风险&#183;分手&#183;点火

不利苗头显露出时,不是简单地扼杀于摇篮之中,反而四处煽风点火,主动将局面导入更加混乱、更加危险的地步。补锅是一门老手艺,补锅匠为客户补锅的时候,一定是拿到破锅先敲三敲,借以判断破损的位置及程度,然后就会和客户商量说:这锅某处有3分长的裂缝,需要将敲它到5分,才方便下手修补,如何?李宗吾据此引申出一个“补锅法”:凡你需要解决任何问题,一定要想方设法先将该问题夸大或搞大,然后再施展各种手段予以解决一