Non-linear regression models for Approximate Bayesian Computation

Approximate Bayesian inference on the basis of summary statistics is well-suited to complex problems for which the likelihood is either mathematically or computationally intractable. However the methods that use rejection suffer from the curse of dimensionality when the number of summary statistics is increased. Here we propose a machine-learning approach to the estimation of the posterior density by introducing two innovations. The new method fits a nonlinear conditional heteroscedastic regression of the parameter on the summary statistics, and then adaptively improves estimation using importance sampling. The new algorithm is compared to the state-of-the-art approximate Bayesian methods, and achieves considerable reduction of the computational burden in two examples of inference in statistical genetics and in a queueing model.     

A computer model for unconscious spread of anxiety-linked inhibition in cognitive networks

Unconscious inhibitory processes, triggered by a potential anxiety reaction, are reviewed in the context of an emerging rapprochement between psychodynamic and cognitive approaches in experimental psychology. Conditions underlying spread of inhibitory action to other cognitive networks are first explored in three tachistoscopic experiments utilizing words posthypnotically tied to a potential anxiety, pleasure, or neutral reaction. Response times of subjects, instructed to ignore those words while naming pictures or solving anagrams as quickly as possible, reveal a highly differentiated pattern of circumstances governing likelihood of inhibitory spread from anxiety-linked words to target stimuli. Next a computer model is constructed to simulate cognitive processes from onset of display to eventual response, and the model is then tested for its fit to the empirical data. Finally, an illustrative study shows that a subset of computer-generated predictions for spread of inhibitory action is verifiable experimentally.     

History of sexual abuse and parental alcohol misuse: Risk,outcomes and protective factors in adolescents

This study examined the school performance, suicidal involvement, disordered eating behaviors, pregnancy risk and chemical use of teenagers with a history of sexual abuse or parental alcohol misuse and found that they had higher rates of these adverse outcomes than among a comparison group of teenagers without such background risk factors. Adolescents with dual-risk background reported higher levels of suicide risk, disordered eating, sexual behaviors and chemical abuse than teenagers with only one background risk factor. Among index group members, protective factors against these adverse outcomes included a high degree of religiosity and the ability to discuss problems with family or friends. Risk factors that increased the likelihood of adverse outcomes included depression, perceived substance use in school and worries about family financial security.The first author was supported in the preparation of this article by a grant from the Lois and Samuel Silberman Fund of New York.     

Unmet service needs of families of young children with chronic illnesses and disabilities

Data about health and educational services were collected from 187 families with young children (under two years) who have chronic illnesses and disabilities. The purpose was to assess parents' satisfaction with services their families received and to identify families' unmet service needs as well as the reasons for these unmet needs. Although families' ratings of the adequacy of services are relatively high, 28% of the families report unmet service needs. The unmet needs most often reported are occupational, physical, or speech therapy; respite care/child care; and special education. Lack of funding is the most commonly given reason for unmet needs. Children with multiple impairments are at highest risk for unmet needs. Only 22% of unmet needs reported at the initial interview have been met by the time of the six-month follow-up. Increased coordination and monitoring of services across service sectors are indicated. Her research interests include the effects of disability on family identity and families' responses to minority stress. She received her Ph.D. from the University of Minnesota. She gratefully acknowledges Shelley Blazis and Nadav Casuto for statistical consulting. Her research interests focus on the impact of chronic illness and disability on families. She received her Ph.D. from the University of Minnesota. Her research interests include families and health and chronic illness and disability in children. She received her Ph.D. in Family Social Science at the University of Minnesota. His areas of interest include neurodevelopmental outcomes of low birth weight infants and training in developmental pediatrics. He was graduated from the University of Minnesota Medical School. His areas of interest include adolescents with chronic illness and disabilities, adolescent sexual decision making, and international adolescent health care issues. He was graduated from Howard University College of Medicine was awarded his earned doctorate in Health Policy from the University of Minnesota. Preparation of this article was supported by the National Institute on Disability and Rehabilitation Research Grant #H133890012.     

Deceptive Practices in Managing a Family Member with Alzheimer's Disease

Deception in the Alzheimer family shares characteristics with deception in a variety of other settings, in that it becomes routinized and contextualized. However, deception in the Alzheimer family is utilized toward the end of informal social control rather than primarily for information control. A key differentiating feature of the Alzheimer context is the gradually diminishing mental capacity and awareness of the person with the disease. This four-year longitudinal study, involving participant observation of a caregivers' support group and in-depth interviews of its members, examines how deceptive practices are learned; the various forms such practices take, including two-party deception and collusion with others; and conflict posed for the caregiver between treating the family member with dignity and coping with the daily ordeal of managing in the home.