A computationally simple bivariate survival estimator for efficacy and safety

Both treatment efficacy and safety are typically the primary endpoints in Phase II, and even in some Phase III, clinical trials. Efficacy is frequently measured by time to response, death, or some other milestone event and thus is a continuous, possibly censored, outcome. Safety, however, is frequently measured on a discrete scale; in Eastern Cooperative Oncology Group clinical trial E2290, it was measured as the number of weekly rounds of chemotherapy that were tolerable to colorectal cancer patients. For the joint analysis of efficacy and safety, we propose a non-parametric, computationally simple estimator for the bivariate survival function when one time-to-event is continuous, one is discrete, and both are subject to right-censoring. The bivariate censoring times may depend on each other, but they are assumed to be independent of both event times. We derive a closed-form covariance estimator for the survivor function which allows for inference to be based on any of several possible statistics of interest. In addition, we derive its covariance with respect to calendar time of analysis, allowing for its use in sequential studies.     

Bayesian palaeoclimate reconstruction

Summary.  We consider the problem of reconstructing prehistoric climates by using fossil data that have been extracted from lake sediment cores. Such reconstructions promise to provide one of the few ways to validate modern models of climate change. A hierarchical Bayesian modelling approach is presented and its use, inversely, is demonstrated in a relatively small but statistically challenging exercise: the reconstruction of prehistoric climate at Glendalough in Ireland from fossil pollen. This computationally intensive method extends current approaches by explicitly modelling uncertainty and reconstructing entire climate histories. The statistical issues that are raised relate to the use of compositional data (pollen) with covariates (climate) which are available at many modern sites but are missing for the fossil data. The compositional data arise as mixtures and the missing covariates have a temporal structure. Novel aspects of the analysis include a spatial process model for compositional data, local modelling of lattice data, the use, as a prior, of a random walk with long-tailed increments, a two-stage implementation of the Markov chain Monte Carlo approach and a fast approximate procedure for cross-validation in inverse problems. We present some details, contrasting its reconstructions with those which have been generated by a method in use in the palaeoclimatology literature. We suggest that the method provides a basis for resolving important challenging issues in palaeoclimate research. We draw attention to several challenging statistical issues that need to be overcome.     

Revisiting the model of creative destruction: St. Jacobs,Ontario, a decade later

Ten years ago, the model of creative destruction was developed to predict the fate of communities that base their development on the commodification of rural heritage (Mitchell, C.J.A., 1998. Entrepreneurialism, commodification and creative destruction: a model of post-modern community development. Journal of Rural Studies 14, 273–286). Its application to the village of St. Jacobs, Canada, demonstrated that entrepreneurial investment had fostered the creation of a setting for aestheticized consumption. In this paper we demonstrate that creative destruction has continued to unfold in the village over the course of the past decade. The evolutionary path taken is assessed in light of current literature on rural space. It is concluded that to fully understand the transformative process, one must integrate the demands of myriad sub-cultures, whose social relations, ideologies and actions will contribute to the development of a contested landscape of consumption. This finding necessitates that modifications be made to the model and its various stages. The most significant is recognition that the “heritage-scape” is an interim state of landscape change; one that displaces the productivist landscape of the industrial period, and precedes the creation of the “neo-productivist” leisure-scape of post-industrialism. Whether or not such a “final” state is achieved is dictated by the power struggle that inevitably arises amongst sub-cultures engaged in the transformation of rural space.     

Substance use and vulnerability to sexual and physical aggression: a longitudinal study of young adults

Using data from 2,170 individuals who participated in Waves 8 (age 23) and 9 (age 29) of a multiyear panel study, this study examined whether alcohol and marijuana use in young adulthood increase one's risk for experiencing subsequent sexual or physical assault victimization, whether victims' own violent behavior or involvement in the sale of drugs explain any effects of substance use on victimization, and whether these associations differ by gender. Controlling for prior victimization, we found that marijuana use, but not alcohol use, predicted women's and men's subsequent sexual victimization and men's subsequent physical assault victimization, and that heavy alcohol use, but not marijuana use, predicted women's subsequent physical assault victimization. Whereas the links from marijuana use to victimization were explained by users' own violent behavior, the link from alcohol use to women's physical assault victimization was not.     

Demographic and situational factors affecting injury, resistance, completion, and charges brought in sexual assault cases: what is best for arrest?

This study examines demographic and situational factors in an effort to predict whether or not a complainant was injured, used resistance, experienced a completed assault, and whether charges were brought against the offender. If the accused had consumed alcohol or drugs, he was almost seven times more likely to be arrested. The complainant was six times more likely to report rape completion if she had consumed alcohol or drugs and if the complainant fell unconscious at any time during the attack she was significantly less likely to use a resistance strategy. The complainant's use of a compliance strategy at any time during the assault positively predicted not using a physical resistance strategy and sexual assault completion. The reporting of injury positively predicted use a physical resistance strategy and sexual assault completion. If the assault was completed, it was less likely that charges were pressed. Implications of these findings are discussed, and directions for future research are offered.     

Challenging the one-size-fits-all myth: findings and solutions from a statewide focus group of rural social workers

Of America's counties, 76% are rural, comprising 83% of U.S. land and 25% of the American population. Yet most child welfare programs are designed to fit the needs of urban and suburban families. This article reviews the unique needs and assets of rural children and families in Texas. It presents recommendations from a focus group for overcoming the inappropriate transfer of urban models to rural communities.     

Child sexual abuse and attachment theory:are we rushing headlong into another controversy?

The child sexual abuse knowledge base has developed within a highly charged political and social context. As such, early theories of sexual abuse were susceptible to biases that reflected the larger sociocultural context. The purpose of this paper is to consider whether attachment theory as it is applied to child sexual abuse might also be susceptible to such biases. Although this paper concludes that attachment theory can potentially add an important dimension to the conceptualization of child sexual abuse and its dynamics, it is also suggested that attachment theory may remain at risk for becoming a vehicle for transmitting political and ideological agendas.