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31.
We analyse time-varying risk premia and the implications for portfolio choice. Using Markov Chain Monte Carlo (MCMC) methods, we estimate a multivariate regime-switching model for the Carhart (1997) four-factor model. We find two clearly separable regimes with different mean returns, volatilities, and correlations. In the High-Variance Regime, only value stocks deliver a good performance, whereas in the Low-Variance Regime, the market portfolio and momentum stocks promise high returns. Regime-switching induces investors to change their portfolio style over time depending on the investment horizon, the risk aversion, and the prevailing regime. Value investing seems to be a rational strategy in the High-Variance Regime, momentum investing in the Low-Variance Regime. An empirical out-of-sample backtest indicates that this switching strategy can be profitable, but the overall forecasting ability for the regime-switching model seems to be weak compared to the iid model.  相似文献   
32.
Aims: The utilization of healthcare services and costs among patients with cancer is often estimated by the phase of care: initial, interim, or terminal. Although their durations are often set arbitrarily, we sought to establish data-driven phases of care using joinpoint regression in an advanced melanoma population as a case example.

Methods: A retrospective claims database study was conducted to assess the costs of advanced melanoma from distant metastasis diagnosis to death during January 2010–September 2014. Joinpoint regression analysis was applied to identify the best-fitting points, where statistically significant changes in the trend of average monthly costs occurred. To identify the initial phase, average monthly costs were modeled from metastasis diagnosis to death; and were modeled backward from death to metastasis diagnosis for the terminal phase. Points of monthly cost trend inflection denoted ending and starting points. The months between represented the interim phase.

Results: A total of 1,671 patients with advanced melanoma who died met the eligibility criteria. Initial phase was identified as the 5-month period starting with diagnosis of metastasis, after which there was a sharp, significant decline in monthly cost trend (monthly percent change [MPC]?=?–13.0%; 95% CI?=?–16.9% to –8.8%). Terminal phase was defined as the 5-month period before death (MPC?=?–14.0%; 95% CI?=?–17.6% to –10.2%).

Limitations: The claims-based algorithm may under-estimate patients due to misclassifications, and may over-estimate terminal phase costs because hospital and emergency visits were used as a death proxy. Also, recently approved therapies were not included, which may under-estimate advanced melanoma costs.

Conclusions: In this advanced melanoma population, optimal duration of the initial and terminal phases of care was 5 months immediately after diagnosis of metastasis and before death, respectively. Joinpoint regression can be used to provide data-supported phase of cancer care durations, but should be combined with clinical judgement.  相似文献   
33.
MOCT-MOST: Economic Policy in Transitional Economies -  相似文献   
34.
In this article, we use 22 years of data from the German Socio-Economic Panel and information on plant closures to investigate the effects of unemployment on four indicators of unhealthy lifestyles: diet, alcohol consumption, smoking and (a lack of) physical activity. In contrast to much of the existing literature, which unlike our analysis is unable to assess causality, our results provide little evidence that unemployment gives rise to unhealthy lifestyles.  相似文献   
35.
Using British national survey data, this article assesses the impact of unions on management practices to reduce labour costs, implement high‐performance work systems, and make employee welfare provisions. Relative to non‐union workplaces, those with unions are found to have practices which are consistent with ‘mutual gains’ outcomes.  相似文献   
36.
ABSTRACT

This paper explores how diverse stakeholders frame their expectations of Social Impact Bonds (SIBs). Using discourse analysis, the authors examine competing expectations in SIB press releases, showing how they differ between stakeholders, between institutional contexts, and how they evolve over time. The paper highlights how the prioritization of social finance and collaboration discourses privileges the role of private investors, which in turn diminishes the role of service providers as innovators.  相似文献   
37.
In a paper published in this journal, Hellegers et al. [Hellegers, P., D. Zilberman, E. van Ierland, 2001. Dynamics of agricultural groundwater extraction. Ecological Economics, 303-311] analysed a dynamic model of groundwater extraction in which they added the quality dimension of nitrate concentration to an intertemporal model of resource depletion. This contribution shows that the set-up of the model contains a serious mistake which affects the results of the paper and it corrects the results.  相似文献   
38.
Residential mortgage markets in both the United States and Canada have recently been dominated by instruments such as variable-rate and short-term rollover mortgages which require borrowers to assume a greater burden of interest rate risk. An outstanding question is whether this approach to risk allocation is Pareto optimal or whether there are other more effective methods of dealing with the risk created by interest rate volatility. This study examines the potential for shifting this risk from the mortgage market to the financial futures market. After considering the rationale for expecting that neither mortgage borrowers nor lenders wish to absorb the high levels of risk present in the existing financial environment, this study discusses the hedging of interest rate risk through financial futures markets. Empirical tests are then performed to evaluate the effectiveness of U.S. futures markets for hedging positions from the U.S. mortgage market. These results indicate that the interest rate risk inherent in residential mortgages can be substantially shifted through one or more positions in the existing futures contracts and long-term, fixed-rate mortgages may still be financially feasible under conditions of interest rate volatility.  相似文献   
39.
We explore the relationship between firms' characteristics and recruitment strategies. We present a theoretical search model with two search channels: a costly formal channel and a costless informal channel (referrals). We empirically test the model predictions and find that: larger firms search more formally; firms search more formally for high-skilled workers; the positive relationship between firm's size and formal search intensity also holds for firms not using referrals; firms using referrals invest less into formal search compared to firms not using referrals; larger firms hire less often by referrals than smaller firms; and larger search effort leads to more applicants.  相似文献   
40.
Academic and policy debates over climate change risks and policies have stimulated economic research in a variety of fields. In this article I briefly discuss eight overlapping areas of current research in which further effort is particularly warranted. These areas include decision criteria for policy; risk assessment and adaptation; uncertainty and learning; abatement cost and the innovation and diffusion of technology; and the credibility of policies and international agreements. Further analysis in these areas not only will advance academic understanding but also will provide insights of considerable importance to policymakers.  相似文献   
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