Evaluation of vectorization/parallelization techniques: application to nonparametric curve estimation

The simulation of statistical models in a computer is a fundamental aspect of research in the field of nonparametric curve estimation. Methods such as the FFT (Fast Fourier Transform) or WARP (Weighted Average of Rounded Points) have been developed and analysed for computer implementation of the different techniques in this realm, with the aim of reducing the computation time as much as possible. In this work we analyse two techniques with this objective. These are the vectorization of the source code in which the different algorithms are implemented, and their distributed execution. It can be observed that the vectorization of the programs can improve the results obtained with techniques such as the FFT or WARP, or, in some cases, can prevent the use of these.     

Community and social capital in Slovenia—the impact of transition

The transition from socialism to capitalism has many impacts on the everyday life of the people of Slovenia. Amongst others it has an impact on their community ties and their choices regarding participation in public life. Community can enable or diminish the basic processes, such as solidarity, equal choices and opportunities, and respect for the differences that are needed for an inclusive society. This article researches such processes through the concept of social capital and provides some responses necessary for the political and professional planning of social policy and the practice of social services.     

Doubly periodic non-homogeneous Poisson models for hurricane data

Non-homogeneous Poisson processes with periodic claim intensity rate have been proposed as claim counts in risk theory. Here a doubly periodic Poisson model with short- and long-term trends is studied. Beta-type intensity functions are presented as illustrations. The likelihood function and the maximum likelihood estimates of the model parameters are derived.Doubly periodic Poisson models are appropriate when the seasonality does not repeat exactly the same short-term pattern every year, but has a peak intensity that varies over a longer period. This reflects periodic environments like those forming hurricanes, in alternating El Niño/La Niña years. An application of the model to the data set of Atlantic hurricanes affecting the United States (1899–2000) is discussed in detail.     

Quantitative Risk Assessment of FMD Virus Transmission via Water

Foot-and-mouth disease (FMD) is a viral disease of domesticated and wild cloven-hoofed animals. FMD virus is known to spread by direct contact between infected and susceptible animals, by animal products such as meat and milk, by the airborne route, and mechanical transfer on people, wild animals, birds, and by vehicles. During the outbreak of 2001 in the Netherlands, milk from dairy cattle was illegally discharged into the sewerage as a consequence of transport prohibition. This may lead to contaminated discharges of biologically treated and raw sewage in surface water that is given to cattle to drink. The objective of the present study was to assess the probability of infecting dairy cows that were drinking FMD virus contaminated surface water due to illegal discharges of contaminated milk. So, the following data were collected from literature: FMD virus inactivation in aqueous environments, FMD virus concentrations in milk, dilution in sewage water, virus removal by sewage treatment, dilution in surface water, water consumption of cows, size of a herd in a meadow, and dose-response data for ingested FMD virus by cattle. In the case of 1.6 x 10(2) FMD virus per milliliter in milk and discharge of treated sewage in surface water, the probability of infecting a herd of cows was estimated to be 3.3 x 10(-7) to 8.5 x 10(-5), dependent on dilution in the receiving surface water. In the case of discharge of raw sewage, all probabilities of infection were 100 times higher. In the case of little dilution in small rivers, the high level of 8.5 x 10(-3) is reached. For 10(4) times higher FMD virus concentrations in milk, the probabilities of infecting a herd of cows are high in the case of discharge of treated sewage (3.3 x 10(-3) to 5.7 x 10(-1)) and very high in the case of discharge of raw sewage (0.28-1.0). It can be concluded that illegal and uncontrolled discharges of contaminated milk into the sewerage system may lead to high risks to other cattle farms at 6-50 km distance of the location of discharge within one day. This clearly underlines current measures that prohibit such discharges, and also asks for strict control. This risk assessment clearly demonstrated the potential significance of FMD virus transmission via water, and the results will be useful on an international scale, and could also serve as a basis for other FMD risk-assessment models.     

Poverty statics and dynamics: does the accounting period matter?

Any public policy aimed at reducing the effects of deprivation should be aware of the consequences of the use of different income accounting periods on eligibility and subsequent policy evaluation. This study aims to throw some light on the relev-ance of choosing a specific accounting period for public policy evaluation in a European country, in contrast to the existing evidence for the United States. Our analysis indicates that there are some significant differences in the results on poverty when using different income accounting periods. Researchers and decision-makers using an annual income measure, whatever the economic and social welfare context, should be aware that the use of quarterly data instead of yearly data will lead to a significantly larger number of poor households and a lower level of inequality and mobility in the distribution.     

A class of partially linear single‐index survival models

The authors define a class of “partially linear single‐index” survival models that are more flexible than the classical proportional hazards regression models in their treatment of covariates. The latter enter the proposed model either via a parametric linear form or a nonparametric single‐index form. It is then possible to model both linear and functional effects of covariates on the logarithm of the hazard function and if necessary, to reduce the dimensionality of multiple covariates via the single‐index component. The partially linear hazards model and the single‐index hazards model are special cases of the proposed model. The authors develop a likelihood‐based inference to estimate the model components via an iterative algorithm. They establish an asymptotic distribution theory for the proposed estimators, examine their finite‐sample behaviour through simulation, and use a set of real data to illustrate their approach.     

产出与经济效益的相应关系研究

在文献[1～4]的基础上,进一步提出产出-完全经济效益传递系数、贡献系数和受益系数,以揭示产出与经济效益的相互联系和数量关系,并在此基础上提出了提高各部门经济效益的主要途径。     

Relationships between leadership and professionals' job attitudes and perceptions: Comparison of two leadership models

The aim of this study was to investigate the power of the Average Leadership Style (ALS) and Vertical Dyad Linkage (VDL) models of leadership in explaining relationships between leader's initiating structure behaviour and consideration behaviour, and subordinates' attitudes and perceptions. The considered dependent variables were five facets of job satisfaction, two role stress variables (role conflict and ambiguity), one role strain indicator (job tension), and four dimensions of workteam climate. The relationships were investigated in two occupational samples comprising 127 family physicians and 155 nurses working in 28 Primary Health Care Teams. Within and between analysis (WABA) and contextual analysis were applied in order to determine the appropriate level of analysis (group as expected from ALS or individual as expected from VDL) for studying the relationships between leader consideration and initiating structure behaviours and the dependent variables. The results obtained showed the prevalence of the VDL model in most of the cases, although two of the relationships studied fitted the ALS model.     

Anabolic responses to resistance training in older men and women: a brief review

Resistance training has been shown to be the most effective exercise mode to induce anabolic adaptations in older men and women. Advances in imaging techniques and histochemistry have increased the ability to detect such changes, confirming the high level of adaptability that remains in aging skeletal muscle. This brief review presents a summary of the resistance-training studies that directly compare chronic anabolic responses to training in older (>60 years) men and women. Sixteen studies are summarized, most of which indicate similar relative anabolic responses between older men and women after resistance training. Relatively small sample sizes in most of the interventions limited their ability to detect significant sex differences and should be considered when interpreting these studies. Future research should incorporate larger sample sizes with multiple measurement time points for anabolic responses.