Adaptive Test for Testing the Difference in Survival Distributions

An adaptive test is proposed for the problem of testing the difference in survival distributions when the shape of the hazard ratio is unknown, hence the efficient test is unknown. The proposed adaptive test selects a test statistic from a finite set of the weighted logrank statistics T on the basis of the estimates of the efficiencies of the tests in T for given data. The efficiency estimator uses the length of the test based nonparametric confidence interval for the shift in a time transformed shift model. The suggested adaptive test is shown to be asymptotically efficient among the tests in T under the time transformed shift model and conditions commonly used in survival analysis. Simulations demonstrate that the adaptive test enjoys good small sample properties and in most situations is more powerful than the test using the maximum of the tests in T.     

The interpretation and role of work-associated accelerated childbearing in post-war Britain

The paper examines a variety of data relating to work-associated differentials in birth-spacing and concludes that these may be interpreted as work-motivated. Two effects of employment on fertility are hypothesized: current work exerting a negative, decelerating influence and prospective employment a positive, accelerating influence. It is argued that the post-war rise in fertility to the mid-60s may have been brought about, in part, by the strong trend in women's labour-force participation. The ‘pull’ of future work is argued to have been stronger during the 1950s and 1960s and that of current economic activity to have increased during the 1970s. The changing balance of attractiveness between current and prospective economic activity may therefore initially have had an accelerating and later a decelerating impact on birth rates.     

Structural funds the challenge for sustainable development and regional disparity in the Slovak Republic

The countries of Central and Eastern Europe have undergone unprecedented political and economic changes since the fall of the Berlin Wall in 1989. The EU responded by providing political and financial support for the difficult transformation of these countries and refocused its policies towards the strategy of preparing associate countries for membership. This strategy, commonly known as the ‘pre‐accession strategy’, has three main instruments: European Agreements, structured dialogue and the PHARE programme. After a short delay in the negotiation process caused by political instability, the Slovak Republic has been offered membership in the EU, together with nine other candidates, in May 2004.

The transition process from a command‐and‐control economy to a market economy and a democratic society addressed the issue of the numerous differences in the regions in the Slovak Republic. The high disparity in economic development and low competitiveness of the regions with a resultant dramatic rise in unemployment in a number of ‘low‐income regions’ are some of the major observations. Rather than a result of its rural character alone, the main reason for regional disparity in the Slovak Republic is the deformation of historical relationships in rural areas as a result of industrialization and the intensification of agriculture in the command‐and‐control economy of the past. This led to a distortion of traditional farming habits as well as environmental damage to agricultural land and forests. In addition, the environmental infrastructure (sewerage, water treatment, etc.) is underdeveloped in these regions. Environmental protection and its infrastructure thus play a significant role in the regional disparity of the Slovak Republic and the approximation of the Slovak Republic in the environmental sector can provide double dividends for these low‐income regions. This paper analyses the above‐mentioned regional disparities and tries to identify reasons and measures particularly regarding sustainable development. It also discusses the pre‐accession period failures and successes that can be taken as a learning experience in regard to the financial opportunities of Structural Funds that will emerge upon entering the European Community in May 2004. The paper contains information available prior to February 2003.     

DeFinettian Consensus

It is always possible to construct a real function , given random quantities X and Y with continuous distribution functions F and G, respectively, in such a way that (X) and (Y), also random quantities, have both the same distribution function, say H. This result of De Finetti introduces an alternative way to somehow describe the `opinion' of a group of experts about a continuous random quantity by the construction of Fields of coincidence of opinions (FCO). A Field of coincidence of opinions is a finite union of intervals where the opinions of the experts coincide with respect to that quantity of interest. We speculate on (dis)advantages of Fields of Opinion compared to usual `probability' measures of a group and on their relation with a continuous version of the well-known Allais' paradox.     

Contribution of mental workload to job stress in industrial workers

This study's central objective is to determine how several individual, organizational and ergonomic factors influence the relationship between job stress and mental workload for workers in an electronics company. A cross-sectional study was made as a test of hypotheses regarding that relationship. The sample is composed of 95 workers, of both sexes, from the electronics industry in the metropolitan zone of Guadalajara, Jalisco, Mexico. Ergonomic conditions were evaluated with the Ergonomic Evaluation List, stress was evaluated by administering the SWS-Survey to groups of subjects, and mental workload was evaluated with the NASA-TLX Workload Index. Using Cochran's and Mantel-Haenzsel statistics, the odds ratio for each of the independent variables was {e}stimated as a risk factor for job stress, and analysis was later conducted by means of logistic regression for those risks found to be significant. Of the 95 worker participants, 26.3% presented a high level of job stress and 17.9% of the workers were found to present high levels of mental workload. The results show that working hours, mental demand, temporal demand, and frustration when faced with a given task may be considered risk factors for job stress.     

Interdisciplinary team discussion on work environment issues related to low back disability: a multiple case study

From both a social and cost-benefit perspective, disability prevention and associated management strategies for assisting employees with back pain are only successful if they address critical return-to-work (RTW) determining factors present in the workplace, including ergonomic factors. Despite our current knowledge of the importance of an integrated team approach targeting these factors, questions remain regarding the conceptual framework adopted by contemporary rehabilitation teams as it relates to work-oriented interventions to accommodate employees back to work. The purpose of this study was to explore and describe the work environment issues discussed by an interdisciplinary team engaged in the work rehabilitation process of low back disability cases. A qualitative content analysis was conducted for 10 sample cases that underwent a rehabilitation program in Quebec (Canada). Drawing on the results of these analyses, a framework representing a synopsis of practitioners' involvement in the person-environment dynamic is presented and discussed. This study makes a unique contribution to the understanding of the 'real-life' content of an interdisciplinary activity in disability management, thus, helping rehabilitation practitioners to build knowledge on the practical application of a cross-disciplinary framework to address work environment issues during the RTW process of those patients sick-listed due to back pain.     

Adaptation and Validation of the Polymorphous Prejudice Scale (PPS) - A Short Form In a Sample of Heterosexual Chilean College Students

ABSTRACT. Objectives: The purpose of this article is to present the psychometric characteristics of a short form of the Polymorphous Prejudice Scale (PPS; Massey, 2009), which was adapted and validated in a heterosexual Chilean population. PPS is a multidimensional measure of sexual prejudice. Methods: A nonprobabilistic (convenience) sample consisted of 422 college students. Results: Findings reveal a shortened 16-item form, grouped in four subscales, with all of the items referring to new forms of sexual prejudice. The findings showed differences based on gender, religiosity and geographic location, as hypothesized. Conclusions: Results are discussed in relation to the strengths and weaknesses of the short form of the PPS.     

Statistical models for disaggregation and reaggregation of natural gas consumption data

In this paper, we present a unified framework for natural gas consumption modeling and forecasting. This consists of models of GAM class and their nonlinear extension, tailored for easy estimation, aggregation and treatment of the delayed relationship between temperature and consumption. Since the consumption data for households and small commercial customers are routinely available in many countries only as long-term sum meter readings, their disaggregation and possibly reaggregation to different time intervals is necessary for a variety of purposes. We show some examples of specific models based on the presented framework and then we demonstrate their use in practice, especially for the disaggregation and reaggregation tasks.