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1.
We consider importance sampling (IS) type weighted estimators based on Markov chain Monte Carlo (MCMC) targeting an approximate marginal of the target distribution. In the context of Bayesian latent variable models, the MCMC typically operates on the hyperparameters, and the subsequent weighting may be based on IS or sequential Monte Carlo (SMC), but allows for multilevel techniques as well. The IS approach provides a natural alternative to delayed acceptance (DA) pseudo-marginal/particle MCMC, and has many advantages over DA, including a straightforward parallelization and additional flexibility in MCMC implementation. We detail minimal conditions which ensure strong consistency of the suggested estimators, and provide central limit theorems with expressions for asymptotic variances. We demonstrate how our method can make use of SMC in the state space models context, using Laplace approximations and time-discretized diffusions. Our experimental results are promising and show that the IS-type approach can provide substantial gains relative to an analogous DA scheme, and is often competitive even without parallelization.  相似文献   
2.
The debate on strategic spatial planning highlights the limitations of statutory land use planning in weighing up future options for spatial development, particularly in instances of rapid change. This paper draws on this debate in order to analyse planning institutions and practices in Finland. The case in point is the south-eastern border region where interdependencies with Russia, particularly shopping tourism, have created pressures on land use and led to contentious planning processes between regional and central levels of government. It is argued that, in the absence of cross-border spatial co-ordination, there is a need to establish links between regional land use planning and visions of spatial scenarios in the national context.  相似文献   
3.
Western societies have experienced an increasing flexibilization and deregulation of their labour markets in the last decades. These developments led to an expansion of non-standard work as well as low-paid employment. Nevertheless, there has been little systematic research on flexibilization and low-paid employment in Austria. Against this background, we discuss the growth of low-wages in Austria and analyse which social groups are especially affected by lowpaid work, using data from EU-SILC as well as ECHP for the years 1996–2010. While we find that those with better qualification tend to be better protected against low-pay risks, our results underline that employees in personal services and hospitality industry as well as non-standard workers are increasingly exposed to low-pay risks in the last 15 years.  相似文献   
4.
This paper examines ways of managing testing more efficiently and effectively. The importance and the workload of testing have been growing constantly in the telecommunication industry, as a result of shorter product lifecycles and decreased time-to-market. At the same time, the complexity of products has increased with a decrease in physical dimensions. Managers face enormous challenges in developing knowledge and effective testing processes. This case study proposes the application of two models, a testing optimization model and an extended V2M2 (Verification Validation Maturity Model) model, for managing the value of testing. In the empirical part of the study, the present state of testing management is examined.  相似文献   
5.
Abstract

Open Access is increasingly considered the most logical and hopeful solution to ease the burden on library budgets, as well as the best way to unshackle research findings—its primary role. But is Open Access the panacea for all the ills that currently beset those of us dedicated to the dissemination and preservation of good quality academic research? In this article, Richard Gedye (Sales Director, Oxford Journals) explores the background to one of Oxford Journals' current Open Access initiatives and explains some elements of the model adopted. He also offers his personal opinions on the significant role librarians could play in the Open Access story.  相似文献   
6.
The well-being and safety of children and young people are important aspects in all contexts of everyday life. In particular, a feeling of insecurity might be a problem when being alone. Bullying is also common among school-age children and teenagers. Hence, there is a great need for personalized support systems to resolve these problems. This article describes a new area of research in sensor and social web development to help indicate children’s insecurity in their daily environment. Deeper integration of sensors and the social web would allow us to foresee drastic changes in communities and new social–ethical scenarios will emerge.  相似文献   
7.
In this paper we analyze the preferences about job security using tools from behavioral economics. We focus on the non-pecuniary value of job security and specifically whether this value depends on the current position of employees as tenured or non-tenured. Using a sample of 107 Israeli social workers, randomly allocated between tenured and non-tenured positions, we demonstrate that the non-pecuniary value of job security is about 20% of the wage. We also found that this value depends on the point of reference of the employees. Those with tenure place a higher value on job security, as do those with a higher level of loss aversion.  相似文献   
8.
This randomized, controlled trial evaluated the effects of exercise on health-related quality of life (HRQoL) and fear of falling (FoF) among 149 home-dwelling older women. The 12-mo exercise program was intended to reduce the risk of falls and fractures. HRQoL was assessed by the RAND-36 Survey, and FoF, with a visual analog scale, at baseline, 12 mo, and 24 mo. On all RAND-36 scales, the scores indicated better health and well-being. The exercise had hardly any effect on HRQoL; only the general health score improved slightly compared with controls at 12 mo (p = .019), but this gain was lost at 24 mo. FoF decreased in both groups during the intervention with no between-groups difference at 12 or 24 mo. In conclusion, despite beneficial physiological changes, the exercise intervention showed rather limited effects on HRQoL and FoF among relatively high-functioning older women. This modest result may be partly because of insufficient responsiveness of the assessment instruments used.  相似文献   
9.
Fine particle (PM(2.5)) emissions from traffic have been associated with premature mortality. The current work compares PM(2.5)-induced mortality in alternative public bus transportation strategies as being considered by the Helsinki Metropolitan Area Council, Finland. The current bus fleet and transportation volume is compared to four alternative hypothetical bus fleet strategies for the year 2020: (1) the current bus fleet for 2020 traffic volume, (2) modern diesel buses without particle traps, (3) diesel buses with particle traps, and (4) buses using natural gas engines. The average population PM(2.5) exposure level attributable to the bus emissions was determined for the 1996-1997 situation using PM(2.5) exposure measurements including elemental composition from the EXPOLIS-Helsinki study and similar element-based source apportionment of ambient PM(2.5) concentrations observed in the ULTRA study. Average population exposure to particles originating from the bus traffic in the year 2020 is assumed to be proportional to the bus emissions in each strategy. Associated mortality was calculated using dose-response relationships from two large cohort studies on PM(2.5) mortality from the United States. Estimated number of deaths per year (90% confidence intervals in parenthesis) associated with primary PM(2.5) emissions from buses in Helsinki Metropolitan Area in 2020 were 18 (0-55), 9 (0-27), 4 (0-14), and 3 (0-8) for the strategies 1-4, respectively. The relative differences in the associated mortalities for the alternative strategies are substantial, but the number of deaths in the lowest alternative, the gas buses, is only marginally lower than what would be achieved by diesel engines equipped with particle trap technology. The dose-response relationship and the emission factors were identified as the main sources of uncertainty in the model.  相似文献   
10.
The aim of this study is to investigate the early development of body mass index (BMI), a standard tool for assessing the body shape and average level of adiposity for children and adults. The main aim of the study is to identify the primary trajectories of BMI development and to investigate the changes of certain growth characteristics over time. Based on our longitudinal data of 4223 Finnish children, we took anthropometric measurements from birth up to 15 years of age for birth years 1974, 1981, 1991 and 1995, but only up to 11 years of age for the birth year 2001. As a statistical method, we utilized trajectory analysis with the methods of nonparametric regression. We identified four main trajectories of BMI growth. Two of these trajectories do not seem to follow the normal growth pattern. The highest growth track appears to yield to a track that may yield to overweight and the low birth BMI track shows that the girls’ track differs that of boys on the same track, and on the normal tracks. The so-called adiposity rebound time decreased over time and started earlier for those on the overweight track. According to our study, this kind of acceleration of growth might be more of a general phenomenon that also relates to the other phases of BMI development. The major change seems to occur especially for those children on high growth tracks.  相似文献   
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