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1.
Growth in overall life expectancy is straining the Social Security budget, and the gap in life expectancy between the rich and poor is widening. Motivated by these facts, this paper does four things. First, we develop a simple way to summarize the degree of progressivity in a Social Security system. Second, we show that growth in the life expectancy gap over the last few decades unwinds three-quarters of the progressivity of the Social Security system. Third, we develop simple reforms to Social Security that maintain the progressivity of the system and restore fiscal solvency. Fourth, we estimate the welfare effects of these potential reforms.  相似文献   
2.
Abstract

Not long after the beginnings of motorization in the early 1900s, deaths and injuries from motor vehicle crashes became a problem in a number of high-income-countries (HIC)s, especially the United States. With the biggest problem the US led early efforts to address this issue, and for six decades these efforts were based on folklore (ie a body of widely held but false or unsubstantiated beliefs). They were not evaluated, but clearly were unsuccessful as crash deaths and injuries continued to rise. It was not until the 1970s that a broader range of countermeasures began to be adopted and was scientifically evaluated, and as a result, crash deaths and injuries declined. This history has important lessons today for many low-and-middle-income countries that have growing numbers of motor vehicle crash deaths and injuries, many of which are pedestrians and motorcyclists. This is because there continue to be advocates for many of the failed approaches (especially educational) that dominated the early efforts in HICs.  相似文献   
3.
We examine risk profiles of the Portuguese stock market index component stocks using a novel approach to the classical capital asset pricing model (CAPM). Specifically, we estimate the CAPM via fractal regressions that allow studying the marginal effects at selected scales. In this way, we can reveal whether the risk is perceived differently by market participants with different investment horizons. Apart from the analysis itself, we provide new statistical insights into the issue of separating and comparing the scale-specific effects with statistical validity. We find several stocks deviating from an expected risk perception homogeneity across investment horizons. This is true for both analysed periods, i.e. before and after the global financial crisis. There are also several stocks that changed their relationship to the market portfolio in between, which has strong implications for possible portfolio construction. The proposed methodology is not limited to financial topics but can be used in any discipline where the scale-specific marginal effects might be of interest.  相似文献   
4.
5.
One of the questions associated with facilitated problem structuring is how the micro level of actors’ multimodal communications, contributes to the emergence of a macro level, framing the possibilities for action in a workshop. This paper shows a way to study this macro level, building the visualization of the conversations’ structure starting from a boundary games theory micro analysis of the interactions. Our empirical evidence comes from following a group of academic consultants working to define a value proposition for their activity. We focus on analyzing two out of nine workshops that were felt diametrically opposite in terms of facilitation and achievements. Moving from the micro towards an upward level, three configurations building the structure are identified—shifting, branching and converging. The work carried out allows us to: (1) visualize the structure of conversations in a problem structuring context, (2) highlight the role of multimodal communications in building the conversations and (3) construct an interpretation bridging the micro and macro readings of a workshop. This knowledge is useful for facilitators guiding the dynamic of a workshop and for researchers looking forward to understanding how micro level interactions build higher levels of the social phenomenon of intervention.  相似文献   
6.
In this paper we investigate the long-run relationship between public debt and economic growth in the Spanish economy for the period 1851–2013. We develop a cliometric analysis of the debt–growth nexus using novel time series methods. We find some support for a negative relationship between both variables, but no clear evidence of a debt threshold. The estimated long-run elasticity in a one-break model shows a tendency to decrease over time from a nonsignificant 0.011 to a ?0.070, indicating that a 10 percentage increase in the public debt-to-GDP ratio is associated with 0.70 percentage points lower real economic growth. Indeed, we find for the first subsample (1851–1939) either “decoupling” or “saturation,” while in the second subsample (1940–2000) the long-run elasticity coefficient becomes negative and significant. When we extend our analysis up to 2013, we find a break in 1971 coinciding with the twilight of Franco’s dictatorship and the Spanish transition to democracy.  相似文献   
7.
In this paper, we consider the problem of assessing the “level of small-worldness” of a graph and of detecting small-worldness features in real networks. After discussing the limitations of classical approaches, based on the computation of network indicators, we propose a new procedure, which involves the comparison of network structures at different “observation scales”. This allows small-world features to be caught, even if “hidden” deeply into the network structure. Applications of the procedure to both simulated and real data show the effectiveness of the proposal, also in distinguishing between different small-world models and in detecting emerging small-worldness in dynamical networks.  相似文献   
8.
Since December 2015, the Federal Reserve has operated a new “floor system” in which it brings about desired changes in its targeted federal funds rate by managing the interest rate it pays on bank reserves and other short‐term liabilities. The design of this new system reflects the tendency of Fed officials to view monetary policy as affecting the economy through Keynesian” interest rate channels. From this Keynesian perspective, policy actions that change the size of the balance sheet are seen as tools for influencing credit market conditions that operate in addition to and independently of the Fed's monetary policy stance. The alternative monetarist framework proposed by the author views monetary policy and its effects as operating through the interaction between money supply and demand. Use of this framework makes clear that, even under a floor system, monetary policy actions designed to affect the aggregate price level and the rate of inflation must be accompanied sooner or later by traditional open market operations that have implications for the size and composition of the Fed's balance sheet. Use of the monetarist framework also underscores the likelihood that the Fed, by paying interest on reserves, has unknowingly contributed to the restrictiveness of its own monetary policies since the financial crisis, a period during which inflation has run consistently below target. More generally, the monetarist framework downplays the importance of the zero lower interest rate bound and suggests that monetary policy could be conducted more effectively by adopting and adhering to a consistent, rule‐like manner during good times and bad.  相似文献   
9.
This paper presents a picture of the landscape of consumer law and policy in Ghana and reviews the scope of protection of consumer interests with specific regard to product safety and liability, consumer sales, and telecommunication services. It assesses the legislative and policy framework on consumer contracts, product safety, and unfair commercial practices; discusses the role of national agencies in enforcing safety standards; and highlights some critical consumer issues in telecommunications service delivery. The paper examines the regulatory framework on other consumer issues such as advertising, labelling, and marketing of consumer products; terms and conditions of consumer contracts; and after sales services including the enforcement of guarantees, warranties, refund, and return policies. The paper also discusses the extent of external influence on the development of consumer law and policy in Ghana and reviews the level of interaction with other legal systems and supranational bodies in the three focal areas. The contribution also explores areas of Ghana’s consumer protection framework which could benefit from guidance from the EU transnational model on consumer protection and makes recommendations for the enhancement of the emerging legislative and policy regime on consumer protection in Ghana.  相似文献   
10.
This study examines the influence of the valence of online customer reviews on sales outcomes based on prospect theory. Numerous studies have revealed the importance of customer reviews in online marketing. However, only few studies have explored the impact of online customer reviews on sales outcomes in the dynamic process. Prior studies in behavioral economics literature have indicated that people differently value gains and losses and that losses have more emotional impact than an equivalent amount of gains. This study verifies whether prospect theory applies to the relation between online customer reviews and sales outcomes. Relevant data were collected from Amazon.co.jp, and three statistical models were employed to investigate the relation between the two factors. Major findings confirm that negative customer reviews considerably impact online sales than positive reviews. Furthermore, the findings indicate that the marginal effects of positive and negative reviews decrease with the increase in their volume. The results of this study will enable marketers to compare the relative sales effects of different types of customer reviews and improve the effectiveness of customer service management.  相似文献   
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