Bayesian analysis of non-negative ar(2) processes

A non-negative AR(2) process with exponentially distributed white noise is investigated in the paper. It is assumed that the autoregressive parameters are random variables with a vague prior density. They can be esto,ated by their posterior expectations. Explicit formulas for these estimators are derived and their strong consistency is proved. An approximation to the estimators is proposed which is easier for calculation. The results are illustrated in a simulation study     

Correlates of physical activity participation in community-dwelling older adults

The authors examined factors related to participation in walking, gardening or yard work, and sports or exercise in 686 community-dwelling adults 60-95 years of age from Wave IV of the population-based Americans' Changing Lives Study. Logistic regression revealed that male gender, being married, and better functional health were associated with greater likelihood of participating in gardening or yard work (p < .05). Male gender, better functional health, and lower body-mass index were independently associated with greater likelihood of walking (p < .05). Increasing age, male gender, higher education, and better functional health were associated with greater likelihood of participating in sports or exercise (p < .05). Subsequent analyses yielded an interaction of functional health by gender in sport or exercise participation (p = .06), suggesting a greater association between functional health and participation in men. Gender and functional health appear to be particularly important for physical activity participation, which may be useful in guiding future research. Attention to different subgroups may be needed to promote participation in specific activities.     

On nonlinear models for time series

The paper is a review of nonlinear processes used in time series analysis and presents some new original results about stationary distribution of a nonlinear autoregres-sive process of the first order. The following models are considered: nonlinear autoregessive processes, threshold AR processes, threshold MA processes, bilinear models, auto-regressive models with random parameters including double stochastic models, exponential AR models, generalized threshold models and smooth transition autoregressive models, Some tests for linearity of processes are also presented.     

What Happened to the Society of Leisure? Of the Gap Between the “Haves” and “Have Nots” (Canadian Time Use and Well-Being Trends)

Canadian time use trends of the past 30 years are examined, using General Social Survey data collected by Statistics Canada in 1981, 1986, 1992, 1998, 2005, and 2010. The article analyses changes in the allocation of time to paid work, domestic work, personal needs, and free time, as well as accompanying changes in perceived time pressure and subjective well-being. The article addresses four questions: (1) Do objectively measured time use trends support optimistic forecasts of the 1960s that transition to post-industrial societies is accompanied by substantial gains of free time? (2) Did the time use changes of the past 30 years affect different population and lifecycle groups evenly or asymmetrically? (3) Is there an accord or discord between the objective measures of time use and subjective feelings of time pressure? (4) What are the emotional, and socio-political implications of the observed time use trends?     

Searching for effective interventions for foster children under stress: a meta‐analysis

Foster children experience a lot of stress because of their life histories and changes in their family circumstances, such as foster care placement. It is important that foster parents recognize the early signs of stress in foster children and learn how to act in a non‐threatening and understanding manner. Family‐based interventions may help in this. In this paper, we report on a meta‐analysis of studies (n= 19) of the effectiveness of such interventions. All studies used a pre‐test/post‐test design. Both problem behaviour in foster children and the parenting skills of foster parents improved by 30%; however, none of the interventions were specifically intended to help young children (<4 years) to cope with stress. The importance of interventions for young foster children is discussed, as well as the necessary elements these interventions should include.