The Emerging Problems of Alcohol and Substance Abuse in Late Life

Treatment of substance abuse among older adults will become increasingly important as the number of aged Americans increases. The abuse of psychoactive substances is a major contributor to excess morbidity, mortality, and homelessness among persons of all ages and socioeconomic strata regardless of race or ethnicity. Alcohol and tobacco accountfor the majority of substance abuse-related death and disability in the United States; the former through cerebrovascular and hepatic disease, accidents and violence, the latter through chronic pulmonary disease and malignancy. Patterns of substance abuse in late life are substantially different from those observed among younger adults. However, treatment may be less challenging. Effective diagnosis and treatment requires a nonpunitive, supportive, but persistent approach. This means the capacity to collect a substance intake history and the ability to formulate a treatment plan or referral strategy to an addiction specialist or residential treatment setting. It is also important for the practitioner to manage negative feelings toward patients who decline treatment or who are chronic abusers.     

Simultaneous Confidence Bands for Linear Regression with Covariates Constrained in Intervals

Abstract. The focus of this article is on simultaneous confidence bands over a rectangular covariate region for a linear regression model with k>1 covariates, for which only conservative or approximate confidence bands are available in the statistical literature stretching back to Working & Hotelling (J. Amer. Statist. Assoc. 24 , 1929; 73–85). Formulas of simultaneous confidence levels of the hyperbolic and constant width bands are provided. These involve only a k‐dimensional integral; it is unlikely that the simultaneous confidence levels can be expressed as an integral of less than k‐dimension. These formulas allow the construction for the first time of exact hyperbolic and constant width confidence bands for at least a small k(>1) by using numerical quadrature. Comparison between the hyperbolic and constant width bands is then addressed under both the average width and minimum volume confidence set criteria. It is observed that the constant width band can be drastically less efficient than the hyperbolic band when k>1. Finally it is pointed out how the methods given in this article can be applied to more general regression models such as fixed‐effect or random‐effect generalized linear regression models.     

The Emerging Problems of Alcohol and Substance Abuse in Late Life

Treatment of substance abuse among older adults will become increasingly important as the number of aged Americans increases. The abuse of psychoactive substances is a major contributor to excess morbidity, mortality, and homelessness among persons of all ages and socioeconomic strata regardless of race or ethnicity. Alcohol and tobacco account for the majority of substance abuse-related death and disability in the United States; the former through cerebrovascular and hepatic disease, accidents and violence, the latter through chronic pulmonary disease and malignancy. Patterns of substance abuse in late life are substantially different from those observed among younger adults. However, treatment may be less challenging. Effective diagnosis and treatment requires a nonpunitive, supportive, but persistent approach. This means the capacity to collect a substance intake history and the ability to formulate a treatment plan or referral strategy to an addiction specialist or residential treatment setting. It is also important for the practitioner to manage negative feelings toward patients who decline treatment or who are chronic abusers.     

The Game of Contacts: Estimating the Social Visibility of Groups

Estimating the sizes of hard-to-count populations is a challenging and important problem that occurs frequently in social science, public health, and public policy. This problem is particularly pressing in HIV/AIDS research because estimates of the sizes of the most at-risk populations-illicit drug users, men who have sex with men, and sex workers-are needed for designing, evaluating, and funding programs to curb the spread of the disease. A promising new approach in this area is the network scale-up method, which uses information about the personal networks of respondents to make population size estimates. However, if the target population has low social visibility, as is likely to be the case in HIV/AIDS research, scale-up estimates will be too low. In this paper we develop a game-like activity that we call the game of contacts in order to estimate the social visibility of groups, and report results from a study of heavy drug users in Curitiba, Brazil (n = 294). The game produced estimates of social visibility that were consistent with qualitative expectations but of surprising magnitude. Further, a number of checks suggest that the data are high-quality. While motivated by the specific problem of population size estimation, our method could be used by researchers more broadly and adds to long-standing efforts to combine the richness of social network analysis with the power and scale of sample surveys.     

Facets of an Assignment Problem with 0–1 Side Constraint

We show that the problem of finding a perfect matching satisfying a single equality constraint with a 0–1 coefficients in an n × n incomplete bipartite graph, polynomially reduces to a special case of the same peoblem called the partitioned case. Finding a solution matching for the partitioned case in the incomlpete bipartite graph, is equivalent to minimizing a partial sum of the variables over = the convex hull of incidence vectors of solution matchings for the partitioned case in the complete bipartite graph. An important strategy to solve this minimization problem is to develop a polyhedral characterization of . Towards this effort, we present two large classes of valid inequalities for , which are proved to be facet inducing using a facet lifting scheme.