The nature of the connection between life course and satisfaction with community services

Research on satisfaction with community services has used both age and life cycle stage as predictors of satisfaction. As both age and life cycle stage are indicators of life course, their relative advantages in service satisfaction research need to be assessed. The authors correlated both age and life cycle stage with twenty service satisfaction items and with item non-response (a measure of the salience of a service). Results were: (1) associations with service satisfaction were linear, (2) some associations with salience were markedly curvilinear, and (3) as predictors of service satisfaction, age and life cycle performed similarly. The choice between age and life cycle as predictors of service satisfaction appears to involve conceptual as well as empirical issues.     

Predicting continued use of marijuana among adolescents: the relative influence of drug-specific and social context factors.

Most research on the determinants of adolescent drug use has focused on predictors of either initiation or current use. Little attention has been given to the determinants of continued use of drugs after initiation, even though some researchers have found that the consequences of continued use are more serious than those associated with experimental or occasional use. In this study, a longitudinal sample of 456 secondary and high school students who had already tried marijuana was used to examine the determinants of continued use of marijuana. Nearly 38 percent of those who had tried marijuana continued using, according to the definition operationalized in this study. Potential predictor measures were grouped in a drug-specific domain and a social context domain, and their effects on continued use, controlling for background characteristics, were examined in logistic regression models. Results showed that only the drug-specific domain had a statistically significant effect on the likelihood of continued use. Students who felt that the adverse physical and psychological effects of marijuana were not very important reasons for discontinuing use and those who had gotten stoned during their experimental stage of use were the most likely to continue use after initiation. The results suggest that the perceived physical and psychological effects of the drug are more important determinants of continued use than are social factors or benefits related to use. Any relationships between social factors and continued use are mediated by the perceived effects and risks of the drug.     

The Use of Multiplicity in a Household Survey of Disabilities

The multiplicity technique has been proposed (Sirken, 1970) as a means of improving estimates of the number of rare “events” in a population. This paper describes one use of this technique, namely estimation of the number of persons with certain types of disability living in private dwellings in Canberra. The results are taken from three household surveys conducted in Canberra during 1978–79 in which a multiplicity rule linking parents, siblings and children of residents of sample households who were also living in private dwellings in Canberra was used. While no direct evidence on the level of non-sampling error is available here, it appears that net response errors at least are not substantial using this multiplicity rule and that a reasonable gain in sampling efficiency results from the use of multiplicity.     

Minimax subset selection for the multinomial distribution

Let (X₁,…,X_k) be a multinomial vector with unknown cell probabilities (p₁,?,p_k). A subset of the cells is to be selected in a way so that the cell associated with the smallest cell probability is included in the selected subset with a preassigned probability, P¹. Suppose the loss is measured by the size of the selected subset, S. Using linear programming techniques, selection rules can be constructed which are minimax with respect to S in the class of rules which satisfy the P¹-condition. In some situations, the rule constructed by this method is the rule proposed by Nagel (1970). Similar techniques also work for selection in terms of the largest cell probability.     

Muscle-power quality: does sex or race affect movement velocity in older adults?

To determine sex and race differences in muscle power per unit of muscle contraction, knee-extensor muscle power normalized for knee-extensor muscle volume was measured in 79 middle-aged and older adults (30 men and 49 women, age range 50-85 years). Results revealed that women displayed a 38% faster peak movement velocity than men and African Americans had a 14% lower peak movement velocity than Whites of a similar age when expressed per unit of involved muscle (p < .001). As expected, men exhibited greater knee-extensor strength and peak power per unit of muscle than women, but women had a faster knee- extension movement velocity per unit of muscle than men at the same relative strength level. Moreover, African Americans had greater knee-extensor muscle volume than Whites but exhibited lower knee-extensor strength and lower movement velocity per unit of muscle when tested at the same relative strength levels.