Computationally simple estimation and improved efficiency for special cases of double truncation

Doubly truncated survival data arise when event times are observed only if they occur within subject specific intervals of times. Existing iterative estimation procedures for doubly truncated data are computationally intensive (Turnbull 38:290–295, 1976; Efron and Petrosian 94:824–825, 1999; Shen 62:835–853, 2010a). These procedures assume that the event time is independent of the truncation times, in the sample space that conforms to their requisite ordering. This type of independence is referred to as quasi-independence. In this paper we identify and consider two special cases of quasi-independence: complete quasi-independence and complete truncation dependence. For the case of complete quasi-independence, we derive the nonparametric maximum likelihood estimator in closed-form. For the case of complete truncation dependence, we derive a closed-form nonparametric estimator that requires some external information, and a semi-parametric maximum likelihood estimator that achieves improved efficiency relative to the standard nonparametric maximum likelihood estimator, in the absence of external information. We demonstrate the consistency and potentially improved efficiency of the estimators in simulation studies, and illustrate their use in application to studies of AIDS incubation and Parkinson’s disease age of onset.     

Covariate-defined latent space random effects model

Latent factor models are a useful and intuitive class of models; one limitation is their inability to predict links in a dynamic network. We propose a latent space random effects model with a covariate-defined social space, where the social space is a linear combination of the covariates as estimated by an MCMC algorithm. The model allows for the prediction of links in a network; it also provides an interpretable framework to explain why people connect. We fit the model using the Adolescent Health Network dataset and three simulated networks to illustrate its effectiveness in recognizing patterns in the data.     

Self-Reported Incidence of Physical Violence in College Students

Abstract

A survey of a college student population indicates that physical abuse is prevalent in our society. The self-reported data were found to be similar to that occurring in the literature on parent-reported child abuse, documenting that approximately one-third of college students had a history of moderate abuse and 5 to 10% had a history of a severe abuse during their developmental years. Through an awareness of its high prevalence, the health care provider will question a history of physical violence when evaluating a student with a medical or psychosocial complaint and appropriately plan a management program including therapeutic counseling to decrease the effect of the prior or current physical abuse.     

RURALIZING THE CITY: THE GREAT MIGRATION AND ENVIRONMENTAL REHABILITATION IN BALTIMORE,MARYLAND

This article examines the discursive and material presence of the “rural” in the “urban,” relating it to the historical and contemporary production of African American culture and identity. By using the case of the Great Migration, it discusses how African Americans negotiated and shaped their urban surroundings and formed individual and collective identities by drawing on their rural, southern histories. It then suggests the relevance of these broad historical processes to contemporary analyses and interventions in the urban environment of Baltimore, Maryland. This article challenges assumptions that obscure the agency of urban residents in the formation of identity and the establishment of community. It demonstrates ways in which the historical movement from rural South to urban North was accompanied by a range of cultural resources that have been adapted, discarded, or reconstructed.     

About the contributors

The paper reports secondary analysis of data from the 2010 British Gambling Prevalence Survey, a household survey of a representative sample of the population aged 16 years and over (N = 7756). Responses to questions about frequency of gambling and average monthly spend on each of 15 forms of gambling, and responses to two different problem gambling screens (DSM-IV and PGSI), were used to derive estimates, for each form of gambling separately, of the percentage of (1) all days play (two estimates), and (2) all spend (four estimates), attributable to problem gamblers. Although these estimates must be treated as approximations only, they demonstrate that problem gamblers make a far greater contribution to total gambling attendances and losses than problem gambling prevalence figures would suggest. There are certain forms of British gambling to which problem gamblers may be contributing as much as 20–30% of all days play and spend, and moderate risk gamblers a possible further 10–20%.     

Maternal mental health in Australia and New Zealand: A review of longitudinal studies

AimThe aim of this paper is to describe the factors that impact on the mental health of Australian and New Zealand (NZ) women in the perinatal period (pregnancy and the year following birth), and to determine the impact of perinatal mental health on women's subsequent health by summarising findings from prospective longitudinal studies conducted in Australia and NZ.MethodsA systematic search was conducted using the databases, Scopus, Medline, PsychInfo and Health Source to identify prospective longitudinal studies focused on women's social and emotional health in the perinatal period. Forty-eight papers from eight longitudinal studies were included.ResultsThe proportion of women reporting depressive symptoms in the first year after birth was between 10 and 20% and this has remained stable over 25 years. The two strongest predictors for depression and anxiety were previous history of depression and poor partner relationship. Importantly, women's mood appears to be better in the first year after birth, when compared to pregnancy and five years later. Becoming a mother at a young age is by itself not a risk factor unless coupled with social disadvantage. Women report a high number of stressors in pregnancy and following birth and the rate of intimate partner violence reported is worryingly high.ConclusionMidwives have an important role in the identification, support and referral of women experiencing mental health problems. As many women do not seek help from mental health services, the potential for a known midwife to impact on women's mental health warrants further examination.     

Reducing child poverty by promoting child well-being: Identifying best practices in a time of great need

Child poverty in the United States persists despite a range of social services designed to reduce poverty rates and improve the economic self-sufficiency of families. The economic downturns resulting in job losses and the housing crisis have converged to create a new group of families who were managing to remain out of poverty prior to the recession but are now slipping into poverty, putting additional strain on services. In light of these pressing issues, this article synthesizes the literature examining child poverty to take a long-range view of the relationship between economic strain, system involvement, and impacts on children and the systems attempting to serve these children. The effectiveness of various policy and program efforts aimed at reducing child poverty rates and/or ameliorating the negative effects of living in poverty is reviewed. The article concludes by suggesting a major shift in focus from reducing child poverty as a singular goal to a comprehensive approach to promoting child and family well-being.