On fiducial generators

Fiducial inference has been gaining presence recently and it is the intention of the present article to look at the notion of fiducial generators; meaning procedures to simulate parameter values that in some sense correspond to simulations from some implicit fiducial distribution. It is well known that when the distribution has group structure, stemming from the natural pivotal associated, a fiducial may be obtained. It is in the non group distributions that there appears to be still room for finding a fiducial distribution. Recently some general procedures have been proposed for dealing with generalized fiducials, but these depend on certain choices for a structural equation or a fiducial equation, as in Hannig (2009 Hannig, J. (2009). On generalized fiducial inference. Stat. Sin. 19:491–544.[Web of Science ®] , [Google Scholar]) or Taraldsen and Lindqvist (2013 Taraldsen, G., Lindqvist, B.H. (2013). Fiducial theory and optimal inference. Ann. Stat. 41(1):323–341.[Crossref], [Web of Science ®] , [Google Scholar]), respectively. A brief presentation is made of an earlier approach to fiducial inference for multivariate parameters, as in Brillinger (1962 Brillinger, D.R. (1962). Examples bearing on the definition of fiducial probability with a bibliography. Ann. Math. Stat. 33(4):1349–1355.[Crossref] , [Google Scholar]), and the implied fiducial generator introduced in Engen and Lillegård (1997 Engen, S., Lillegård, M. (1997). Stochastic simulation conditioned on sufficient statistics. Biometrika 84(1):235–240.[Crossref], [Web of Science ®] , [Google Scholar]), trying to connect them. Three interesting non group distributions are seen; two of them, the truncated exponential and the two-parameter gamma, already reported in literature. A third non group distribution is analyzed; the inverse Gaussian, connecting the fiducial that results following Brillinger (1962 Brillinger, D.R. (1962). Examples bearing on the definition of fiducial probability with a bibliography. Ann. Math. Stat. 33(4):1349–1355.[Crossref] , [Google Scholar]), with a result pertaining confidence limits for the shape parameter in Hsieh (1990 Hsieh, H.K. (1990). Inferences on the coefficient of variation of an inverse-Gaussian distribution. Commun. Stat. - Theory Methods 19(5):1589–1605.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]). In the three cases, comparisons are made with the Bayesian posteriors that have been known to be close numerically. Some discussion is made on the issue of singularities of the fiducial density and its connection with densities that do not integrate to unity. As to the case of discrete observables, some comments are made for the Bernoulli distribution, only.     

Multivariate log-Birnbaum–Saunders regression models

In this paper, we present a multivariate version of the skewed log-Birnbaum–Saunders regression model. This new family of distributions holds good properties such as marginal variables following univariate skewed log-Birnbaum–Saunders distributions, besides presenting the usual log-Birnbaum–Saunders distribution as a particular case. Furthermore, the model parameters are estimated through maximum-likelihood methods, a closed-form expression for the Fisher’s information matrix is presented, and testing hypothesis for model parameters is performed. Two real datasets are analyzed and results are discussed.     

Fourier–type tests involving martingale difference processes

We develop testing procedures which detect if the observed time series is a martingale difference sequence. Furthermore, tests are developed that detect change–points in the conditional expectation of the series given its past. The test statistics are formulated following the approach of Fourier–type conditional expectations first proposed by Bierens (1982 Bierens, H. J. (1982). Consistent model speci?cation tests. J. Econometr. 20:105–134.[Crossref], [Web of Science ®] , [Google Scholar]) and have the advantage of computational simplicity. The limit behavior of the test statistics is investigated under the null hypothesis as well as under alternatives. Since the asymptotic null distribution contains unknown parameters, a bootstrap procedure is proposed in order to actually perform the test. The performance of the bootstrap version of the test is compared in finite samples with other methods for the same problem. A real–data application is also included.     

Promoting healthy transition to college through mindfulness training with first-year college students: Pilot randomized controlled trial

Objective: Given the importance of developmental transitions on young adults' lives and the high rates of mental health issues among U.S. college students, first-year college students can be particularly vulnerable to stress and adversity. This pilot study evaluated the effectiveness and feasibility of mindfulness training aiming to promote first-year college students' health and wellbeing. Participants: 109 freshmen were recruited from residential halls (50% Caucasian, 66% female). Data collection was completed in November 2014. Methods: A randomized control trial was conducted utilizing the Learning to BREATHE (L2B) program, a universal mindfulness program adapted to match the developmental tasks of college transition. Results: Participation in the pilot intervention was associated with significant increase in students' life satisfaction, and significant decrease in depression and anxiety. Marginally significant decrease was found for sleep issues and alcohol consequences. Conclusions: Mindfulness-based programs may be an effective strategy to enhance a healthy transition into college.     

Efficiency Analysis of the European Food Banks: Some Managerial Results

Hundreds of thousands of people in Europe are daily receiving food, thanks to local food banks, run basically by volunteers who collect donations and distribute them to organizations. In this paper, data from a sample of food banks working in 13 European countries are analysed using Data Envelopment Analysis (DEA), trying to learn about their profiles and find some clues about the efficiency of their operations, comparing them according to variables such as the number of volunteers and permanent staff, the tonnage of food delivered and the number of people served. Significant inefficiencies were found in the sector as a result of high performance of some food banks, thus setting a high level standard of operational efficiency. Some additional results regarding food bank sizes and performance are presented.     

Influential factors in the choice of public transportation or cars as the mode of transportation in habitual commutes / Factores que influyen en la elección del transporte público o el automóvil como modo de transporte en los desplazamientos habituales

The goal of this study is to analyse the differences in attitudes towards habitual modes of transportation among users of public and private transportation. The explanatory capacity of attitudes when determining the mode choice, along with the structural and sociodemographic factors, are also verified. The study was performed in three Spanish cities with 742 participants. The results revealed that cars are better rated than public modes of transportation in the attributes associated with immediate advantages (i.e., speed and availability) and convenience. Subways are highly rated in both immediate and deferred advantages (environment, safety, cost and health). Buses are the mode rated the lowest of the three. Using logistic regression, it was verified that the variance explained by a model that includes attitudes (R² = .639) is higher than the variance explained by a model based solely on variables related to infrastructures (R² = .489). The discussion of these results includes proposals aimed at decreasing car use.     

Profile of the Present Slovak Society and its Regional Differences

The article is the first attempt in assessment of the development and the present situation of social structure and stratification in Slovakia. Its principal aim is to develop the profile of the present society in Slovakia, which reflects the pace and complexity of the transformation process and its impact on society. Processing of Micro census data from 2003 led to creation of the profile of society in Slovakia at the national level based on income distribution but also knowledge on regional societies and differences between them were obtained. It was found out that the present profile of the society in Slovakia is pear-shaped which means strong representation of lower strata and weaker representation of higher middle and high strata. The profile disclosed some specific features and inconsistencies in the present society of Slovakia, which were, and still are determined by many non standard past and present phenomena and processes often disguised by reforms. The information drawn in regions has facilitated identification of the basic nature and structure of regional societies, some of their specific features and negative elements and to demonstrate their highly differentiated character.

The importance of being mature: the effect of demographic maturation on global per capita GDP

Given that savings behaviour and worker productivity have strong life-cycle components and given that demographic profiles vary across countries, population age structure should be linked to differences in levels of economic development. In this paper, we measure the economic importance of age structure variation for the global economy. We find that demographic maturation has been associated with nearly half of the evolution of global per capita GDP since 1960. We also find that age structure differences can account for just over half of the variation in worldwide per capita GDP (i.e. the lack of sigma convergence) observed since 1960.

Staff Reactions Toward Lesbian,Gay, or Bisexual (LGB) People Living in Residential Aged Care Facilities (RACFs) Who Actively Disclose Their Sexual Orientation

Fifty-three staff members currently working in residential aged care facilities located in Barcelona, Spain, were asked about the way they would react if a resident told them that he or she felt sexually attracted and had maintained sexual relationships with another resident of the same gender. Acceptance of non-heterosexual sexual orientation was a frequent answer, and around one in four professionals stated that they would try helping the resident in question, by offering a private space or giving some emotional support. However, some reactions were not consistent with a respectful approach toward sexual diversity, as, for instance, informing the resident’s family or advising the resident to keep his or her sexual orientation hidden. We highlight the importance of developing formal policies and offering formal training to staff in order to address the specific needs of older LGB people living in RACFs.