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951.
This article presents an empirical analysis of firms' order backlogs, inventories, production, and price adjustments to unanticipated demand shocks. The data are obtained from quarterly INSEE Business Survey Tests on firms' realizations, expectations, and appraisals of some various economic variables. The analysis is based on the formulation and the estimation of a recursive system of conditional log-linear probability models.  相似文献   
952.
Consider classifying an n × I observation vector as coming from one of two multivariate normal distributions which differ both in mean vectors and covariance matrices. A class of dis-crimination rules based upon n independent univariate discrim-inate functions is developed yielding exact misclassification probabilities when the population parameters are known. An efficient search of this class to select the procedure with minimum expected misclassification is made by employing an algorithm of the implicit enumeration type used in integer programming. The procedure is applied to the classification of male twins as either monozygotic or dizygotic.  相似文献   
953.
There are many time series applications where an experi­menter observes the simultaneous responses of several sub­systems over time. In these instances one is often not interested in the parameters of individual subsystems, but rather in an overall characterization of the system in question. Under the assumption that subsystems are independent and first order autoregressive, the present paper presents two methods for estimating the distribution of the subsystem coefficients.  相似文献   
954.
ABSTRACT

The purpose of this qualitative study was to explore the social networks of Appalachian adolescents to understand socialization strategies and goals. A total of 46 interviews were conducted with five families (mothers, fathers, and adolescents) and 11 socialization agents the families identified as exerting significant influence in the lives of the adolescents. Interviews were transcribed and then analyzed using principles of grounded theory. Five themes developed from the interviews: the importance of community to the socialization process, adult involvement and support, adolescent monitoring, teaching respect and responsibility, and adolescent autonomy. Results suggest the need for in-depth investigation of adolescent development within a variety of cultural and social contexts to more fully understand these processes.  相似文献   
955.
This paper discusses the application of a general equilibrium model, developed at Stanford Research Institute, for use in long range forecasting and business planning. The value of the modeling approach is illustrated through application to a hypothetical natural gas liquefaction venture. Specific features and representative output of the SRI model are presented. The authors stress the use of a modeling approach in the planning process as a quantitative means of evaluating the importance of uncertainty in specific decision variables and the ability of such model to test explicitly the long term impact of changes in a given set of base assumptions.  相似文献   
956.
For many diseases, logistic constraints render large incidence studies difficult to carry out. This becomes a drawback, particularly when a new study is needed each time the incidence rate is investigated in a new population. By carrying out a prevalent cohort study with follow‐up it is possible to estimate the incidence rate if it is constant. The authors derive the maximum likelihood estimator (MLE) of the overall incidence rate, λ, as well as age‐specific incidence rates, by exploiting the epidemiologic relationship, (prevalence odds) = (incidence rate) × (mean duration) (P/[1 ? P] = λ × µ). The authors establish the asymptotic distributions of the MLEs and provide approximate confidence intervals for the parameters. Moreover, the MLE of λ is asymptotically most efficient and is the natural estimator obtained by substituting the marginal maximum likelihood estimators for P and µ into P/[1 ? P] = λ × µ. Following‐up the subjects allows the authors to develop these widely applicable procedures. The authors apply their methods to data collected as part of the Canadian Study of Health and Ageing to estimate the incidence rate of dementia amongst elderly Canadians. The Canadian Journal of Statistics © 2009 Statistical Society of Canada  相似文献   
957.
958.
We consider a continuous-time model for the evolution of social networks. A social network is here conceived as a (di-) graph on a set of vertices, representing actors, and the changes of interest are creation and disappearance over time of (arcs) edges in the graph. Hence we model a collection of random edge indicators that are not, in general, independent. We explicitly model the interdependencies between edge indicators that arise from interaction between social entities. A Markov chain is defined in terms of an embedded chain with holding times and transition probabilities. Data are observed at fixed points in time and hence we are not able to observe the embedded chain directly. Introducing a prior distribution for the parameters we may implement an MCMC algorithm for exploring the posterior distribution of the parameters by simulating the evolution of the embedded process between observations.  相似文献   
959.
This study investigates differences between heterosexuals and homosexuals of both sexes with regard to several variables in the career decision-making process: anxiety about making a career choice, indecisiveness about the choice, need to acquire information about the career of choice, uncertainty about the choice, and career choice dissatisfaction. Significant interactions are found on choice uncertainty (gay men having the highest level of uncertainty and lesbian women the lowest) and choice dissatisfaction (heterosexual women and gay men showing more dissatisfaction than the other two groups).  相似文献   
960.
Abstract Mortality levels and differences by metropolitan-nonmetropolitan residence for blacks and whites are examined in the South using life-table techniques. Life tables are constructed for Southern subpopulations using U.S. vital statistics and census data for 1980, and differences in the life expectancies are decomposed by cause of death. Results suggest that life expectancy is higher for metropolitan and white populations. Racial mortality differences are slightly greater in metropolitan areas of the South when compared to the nonmetropolitan South. Residential mortality differences are attributable mainly to differences in the effects of heart disease and accidents. Most of the racial mortality difference is due to differences in effects of malignant neoplasms, cardiovascular disease, perinatal conditions, and homicide. Policy efforts aimed at specific causes of death in specific populations are suggested as a means of reducing racial or residential life expectancy differentials.  相似文献   
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