Cost containment in health care: a model for management research.

Cost containment is a dominant problem in the health care field, but it has not been addressed from a comprehensive management perspective. To fill this gap, we have developed an inclusive model of the cost containment process. The model has implications for management research in several areas: cost containment baselines, incentive systems, organization structures, cost/quality trade-offs, and cost containment constraints.     

Asymptotic properties of the maximum-likelihood estimator for a class of birth-and-death processes admitting a unique stationary distribution

The asymptotic properties of the maximum-likelihood estimator of the parameter vector for a class of birth-and-death processes admitting a unique stationary distribution are studied. Also, it is shown that identifiability of the parameter vector with respect to the likelihood implies that the Fisher information matrix is of full rank. Two special cases of biological interest are presented. One of these, the exponential birth-and-death process, is proposed as a more appropriate model of density dependence than the logistic process.     

Age residential segregation in Canadian cities

Des indices de dissimilitude relativement a la distribution rCsidentielle de la population canadienne sont calculis ici pour les groupes d'ige de plus de 65 ans et de moins de 65 ans, ainsi que par sexe. Les donnPes de toutes les villes compris dans les programmes des secteurs de recensement de 1971 (30 villes), 1976 (32 villes), et 1981 (36 villes) sont utilisCes. L'analyse de I'annPe 1981 prksente un indice moyen de 27.5, pour des valeurs s'khelonnant entre 16.7 et 38.2. Les villes de I'ouest canadien presentent les indices de segregation les plus ClevPs, et les indices des femmes igCes sont plus PlevCs que ceux des hommes du mime ige. Depuis 1971, on note une augmentation de la segregation rksidentielle des personnes igCes, et aussi une augmentation de la difference sur la base du sexe. A partir de la thCorie Ccologique, une explication de la variation d'une ville a I'autre des degres de segrCgation est proposCe, puis est fortement appuyee par I'analyse.
Indexes of dissimilarity, measuring the dissimilarity of residential distribution between the population aged 65 years and over and the population aged under 65, were computed for all tracted cities in the 1971 (30 cities), 1976 (32 cities), and 1981 (36 cities) Censuses of Canada. Separate indexes were computed for elderly males and females. The results show an average index in 1981 of 27.5, and a range of 16.7 to 38.2; with cities in Western Canada having the highest segregation indexes. The indexes were higher for older women than for older men. Trends since 1971 indicate an increasing residential segregation of the aged as a group as well as a widening sex differential among them. An explanation of the variations in segregation levels among the cities based on ecological theory received strong support.     

The rescission of behaviors: Inconsistent responses in adolescent sexuality data

In longitudinal survey research, certain questions can be rescinded illogically. For instance, respondents who at Time 1 report having had sexual intercourse may at Time 2 report never having done so. This paper reports measurement techniques and analyses of these types of inconsistencies from an ongoing longitudinal adolescent sexuality project. Inconsistencies in intercourse, masturbation, and other sexual behaviors are reported and compared to rates from other studies and other less sensitive behaviors within the same study. Three conclusions are presented: (1) inconsistencies should be considered a natural part of any longitudinal survey process and should be incorporated into the response model; (2) inconsistency rates in these particular data support the contention that adolescent sexuality data of appropriate quality for analytical purposes can be obtained; and (3) inconsistency rates in fact contain substantive information concerning the processes under consideration.