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171.
Abstract

This study investigates the risk inherent in defined contribution (DC) pension plans on an individual and aggregate basis, based on U.S. data. Our aim is to gain insight into the consequences of a DC pension scheme becoming the predominant pillar of retirement income for an entire society. Using the stochastic simulated output of a DC flexible age-of-retirement model, we first determine the optimal investment strategies. We then examine the demographic retirement dynamics of an entire population of DC pension plan participants.

We observe that even for the most risk-averse plan members there is a high level of uncertainty in an individual’s age at retirement. At the aggregate population level, we find that this uncertainty does not get dampened to any great extent by a diversification effect. Instead, the central role played by the market in determining retirement dates results in significant variation in the dependency ratio (the ratio of retirees to workers) over time. In addition, an attempt to ameliorate the outcome by introducing additional realistic features in the DC population modeling did little to dampen this volatility, which suggests that countries dominated by DC schemes of this type may, over time, be exposed to significant risk in the size of its labor force.  相似文献   
172.
Since the 1970s technology assessment by public bodies has become generally accepted as necessary. Modes of technology assessment differ from country to country, in terms of degree of institutionalization, acceptance by policy makers and level of public involvement, and these in turn depend on the goals, methods and organizational framework of the particular technology assessment. The varying social and political roles of technology assessment arise out of national political traditions and differing cultural views of technology. This article compares modes of biotechnology assessment in the USA, Japan and Denmark, focusing on the role of public discussion in the policy-making process. By analysing these three different contexts, the article seeks to uncover ways in which the cultural conditioning of technology policy takes place.  相似文献   
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175.
This article appraises the recent UK quantitative easing (QE) monetary experiment. From March 2009 to February 2010, the Bank of England spent £200 billion on gilts and corporate bonds. This experiment represents, as a proportion of GDP, the most ambitious monetary policy ‘mission’ in history. Using several indicators to examine the impact of QE, our analysis leads to a conclusion which, metaphorically, is akin to that ascribed to the 1970 Apollo 13 Moon mission: a ‘successful failure’.  相似文献   
176.
Using a difference-in-differences estimation framework and state-level data, we investigate the potential role of HIV/AIDS in contributing to declining abortion utilization in the United States. Our results suggest that the perceived risk of HIV contraction negatively affected unwanted pregnancies. Specifically, a 10% increase in HIV incidence is associated with 0.34–1.1% fewer abortions per live births, an effect that can account for at least one-tenth of the sharp decline in abortions observed from the early 1980s to mid-1990s.  相似文献   
177.
Hedge funds often impose lockups and notice periods to limit the ability of investors to withdraw capital. We model the investor's decision to withdraw capital as a real option and treat lockups and notice periods as exercise restrictions. Our methodology incorporates time-varying probabilities of hedge fund failure and optimal early exercise. We estimate a two-year lockup with a three-month notice period costs approximately 1% of the initial investment for an investor with constant relative risk aversion utility and risk aversion of three. The cost of illiquidity can easily exceed 10% if the hedge fund manager can arbitrarily suspend withdrawals.  相似文献   
178.
A copula models the relationships between variables independently of their marginal distributions. When the variables are time series, the copula may change over time. Recursive procedures based on indicator variables are proposed for tracking these changes over time. Estimation of the unknown parameters is by maximum likelihood. When the marginal distributions change, pre-filtering is necessary before constructing the indicator variables on which the recursions are based. This entails estimating time-varying quantiles and a simple method based on time-varying histograms is proposed. The techniques are applied to the Hong Kong and Korean stock market indices. Some interesting and unexpected movements are detected, particularly after the attack on the Hong Kong dollar in 1997.  相似文献   
179.
Efforts to reduce greenhouse gas emissions in the residential sector by adopting technologies such as solar photovoltaics and electric vehicles (EVs) have major implications for the capacity of electricity distribution networks, particularly at local areas with high uptake. Consumer decisions to purchase these technologies are also influenced by several complex criteria such as costs/benefits, performance, appeal/status, risk, psychographics, and demographics. This complexity motivated the development of an innovative diffusion model, incorporating features of multi-criteria analysis and choice modelling, to estimate the adoption of these technology options spatially across the landscape of heterogeneous consumers. We test the model to forecast market share of EVs through to 2030, using the vehicle stock across all 1.5 million households in Victoria, Australia. Seven financial and non-financial criteria were included and calibrated via focus groups and a large‐scale survey. Annual change of criteria values and their elasticity to adoption were incorporated. Geographical differences in uptake of EVs were primarily due to driving distance, employment status and household income, with urban areas having about three times the proportional uptake. By testing the model for a range of incentives, we demonstrate its capability to inform and evaluate policy options.  相似文献   
180.
Many theories in finance imply monotonic patterns in expected returns and other financial variables. The liquidity preference hypothesis predicts higher expected returns for bonds with longer times to maturity; the Capital Asset Pricing Model (CAPM) implies higher expected returns for stocks with higher betas; and standard asset pricing models imply that the pricing kernel is declining in market returns. The full set of implications of monotonicity is generally not exploited in empirical work, however. This paper proposes new and simple ways to test for monotonicity in financial variables and compares the proposed tests with extant alternatives such as t-tests, Bonferroni bounds, and multivariate inequality tests through empirical applications and simulations.  相似文献   
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