Data-swapping: A technique for disclosure control

This paper describes data-swapping as an approach to disclosure control for statistical databases. Data-swapping is a data transformation technique where the underlying statistics of the data are preserved. It can be used as a basis for microdata release or to justify the release of tabulations.     

Alcohol abuse on a college campus: A needs assessment

This paper reports the results of a needs assessment study conducted by a university-based alcohol abuse prevention project. Data are presented on the drinking patterns and drinking problems of a random sample of 462 students. Results suggest that students are experiencing numerous difficulties in the physical, educational, legal and psychosocial areas due to their use of alcoholic beverages. Implications for prevention and intervention programming are discussed and the need for planning programs from a data-based perspective rather than a rational and intuitive approach is stressed.     

The impact of state TANF policy decisions on kinship care providers

Based on a survey of public assistance and child welfare agency staff, this article examines how state Temporary Assistance for Needy Families (TANF) policy decisions have affected kinship care providers. Findings indicate that most states have continued using TANF to provide income support to kinship caregivers, and some have used TANF to find related support services. These payments, however, are much lower than rates for licensed providers, and many kinship caregivers are subject to work, training requirements, and time limits.     

Physical activity is associated with better health and psychological well-being during transition to university life

The authors investigated vigorous physical activity, psychological well-being, and self-reported illness during transition to first-year university life in a sample of 175 Canadian undergraduates. At the completion of their first year of university study, participants completed retrospective measures assessing vigorous physical activity, upper respiratory infectious illness (URI), doctor visits, as well as measures of psychological well-being. Based on nationally recommended (US Department of Health and Human Services) standards, 61% of students reported engaging in adequate levels of vigorous activity during their first year at university. The authors found no differences in URIs between sufficiently and insufficiently active students. However, insufficiently active students scored lower on psychological well-being and were twice as likely to have consulted a physician regarding an illness compared with sufficiently active students.     

Employment transitions for clubhouse members

Using a longitudinal dataset which followed 2195 individuals employed in 3379 separate job placements over a four-year period, this paper explores movement between the employment supports, [Transitional (TE), Supported (SE), and Independent Employment (IE)], offered by clubhouses. Sixty-four percent of employed members held only one job (N=1395) and 36% held multiple jobs during the study (N=791). Patterns of movement were consistent for transitions between the first and second job and subsequent transitions. Forty-six percent of individuals holding multiple jobs moved from one employment type to another. When movement occurred clubhouse members were significantly more likely to move from employment types offering more supports to those that offer less supports.     

Endurance exercise and leg strength in older women

Quadriceps strength and mass peak in the third decade of life, plateau, and then decline from the fifth decade on. To examine the influence of chronic endurance training and age on lean mass and leg strength, women runners (n = 62, age 43-69 years) and sedentary participants (n = 33, age 43-66 years) were divided into 40-, 50-, and 60-year age groups. Absolute isokinetic concentric torque did not differ between runners and sedentary women (97.9 +/- 19.5 and 104.6 +/- 22.7 N . m, respectively, p = .18) but was different between age groups independent of exercise status (107.6 +/- 18.4, 97.1 +/- 19.9, and 90.1 +/- 21.4 N . m, for 40s, 50s, and 60s, respectively, p < .05). Lean body mass also differed by age group (p < .05) but did not change differently among runners and sedentary women. These findings suggest that chronic endurance training might not influence the loss of muscle mass and muscle strength that occur with aging.     

Connected Substitutes and Invertibility of Demand

We consider the invertibility (injectivity) of a nonparametric nonseparable demand system. Invertibility of demand is important in several contexts, including identification of demand, estimation of demand, testing of revealed preference, and economic theory exploiting existence of an inverse demand function or (in an exchange economy) uniqueness of Walrasian equilibrium prices. We introduce the notion of “connected substitutes” and show that this structure is sufficient for invertibility. The connected substitutes conditions require weak substitution between all goods and sufficient strict substitution to necessitate treating them in a single demand system. The connected substitutes conditions have transparent economic interpretation, are easily checked, and are satisfied in many standard models. They need only hold under some transformation of demand and can accommodate many models in which goods are complements. They allow one to show invertibility without strict gross substitutes, functional form restrictions, smoothness assumptions, or strong domain restrictions. When the restriction to weak substitutes is maintained, our sufficient conditions are also “nearly necessary” for even local invertibility.     

Optimal spacing of quantiles for the estimation of the mixing parameters in a mixture of two exponential distributions

Methods for estimating the mixing parameters in a mixture of two exponential distributions are proposed. The estimators proposed are consistent and BAN(best asymptotically normal). The optimal spacings for estimating these mixture parameters are calculated.