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931.
This article defines the so called Generalized Matrix Variate Jensen-Logistic distribution. The relevant applications of this class of distributions in Configuration Shape Theory consist of a more efficient computation, supported by the corresponding inference. This demands the solution of two important problems: (1) the development of analytical and efficient formulae for their k-th derivatives and (2) the use of the derivatives to transform the configuration density into a polynomial density under some special matrix Kummer relation, indexed in this case by the Jensen-Logistic kernel. In this article, we solve these problems by deriving a simple formula for the k-th derivative of the density function, avoiding the usual partition theory framework and using a generalization of Pascal triangles. Then we apply the results by obtaining the associated Jensen-Logistic Kummer relations and the configuration polynomial density in the setting of Statistical Shape Theory.  相似文献   
932.
This paper inquires into the kind of desire specific to the fundamentalist mode. The author suggests that the simplistic, black-and-white, ostensibly “horizontal” divisions between good and evil, right and wrong, pure and impure that characterize the fundamentalist sensibility create at the same time two phenomena: (a) gross emotional intensity that endows experience with a stark quality (e.g., grandiosity and abjection), and (b) a “vertical” division that constructs basic inequalities. The “vertical” difference between the believer and his God intensifies longing and mystical desire. The longing of the holder of such desire is to merge with a tantalizing, perfect, and cruel God and to renounce his individuality and even life. The concept of a “regression-to-the father” is a tempting and potentially dangerous process of abnegation if not countered by the need to overcome the “father” one so submissively desires.  相似文献   
933.
934.
935.
This paper presents an analysis of levels of life expectancy and their patterns of change among six socio-economically differentiated sub-populations of England and Wales for the period 1851–1911. Differences in mortality levels among these sub-groups and their rates of change are analyzed with respect to three groups of explanatory variables, viz., environmental, stratification and demographic variables. Their relative importance for different periods is assessed and discussed. The findings show consistency with two previous studies, which have suggested that medical advances had little effect on the increase in life expectancy during the second half of the nineteenth century. The present paper supports the results of one study in that public health measures affected life expectancies earlier, while subsequently, the increase in standards of living was more important.  相似文献   
936.

There are production situations where a production facility (e.g. a machine) is used intermittently to produce lot sizes of certain products. Upon completion of production run, the facility may not be available for a random amount of time due to several reasons, such as: the facility needs to be maintained and the maintenance time is random due to unforeseen circumstances; or that the facility is leased by different manufacturers and the demand for the facility is random. As a result of machine unavailability, stock-out situations might arise. This paper extends the work of Abboud et al . (2000, Computers and Operations Research , 27 , 335-351) by assuming learning and forgetting in production. A new mathematical model is developed with numerical examples and sensitivity analysis provided. Furthermore, this paper determines how the overall inventory cost is influenced by the nature of the random variable that represents the unavailability time of the production facility.  相似文献   
937.
Study of a Markov model for a high-quality dependent process   总被引:1,自引:0,他引:1  
For high-quality processes, non-conforming items are seldom observed and the traditional p (or np) charts are not suitable for monitoring the state of the process. A type of chart based on the count of cumulative conforming items has recently been introduced and it is especially useful for automatically collected one-at-a-time data. However, in such a case, it is common that the process characteristics become dependent as items produced one after another are inspected. In this paper, we study the problem of process monitoring when the process is of high quality and measurement values possess a certain serial dependence. The problem of assuming independence is examined and a Markov model for this type of process is studied, upon which suitable control procedures can be developed.  相似文献   
938.
What is the relationship between well-being and satisfaction of basic psychological needs overtime? The basic psychological needs theory is a subtheory of the self-determination theory that elaborates the concept of psychological needs and its relations to psychological health and well-being. The goals of this research was to establish the causal ordering between basic psychological needs and three psychological well-being indicators (subjective well-being, self-esteem and satisfaction with life), in a longitudinal study. We used a cross-lagged two-wave design. A total of 272 university students completed the questionnaire at the beginning and at the end of the semester. Relatedness at time 1 (T1) had a positive and significant effect on all well-being indicators at time 2 (T2); competence (T1) had a positive and significant effect on all indicators except for self-esteem (T2); finally, autonomy (T1) did not have a significant effect on any of the well-being indicators (T2). In conclusion, we confirm the causal ordering of competence and relatedness on well-being, according to the basic psychological needs subtheory. Universities, in general, and teachers, in particular, should promote relations between students and support the need of competence.  相似文献   
939.
In 2010 the Danish regions started a new program of public health surveillance in collaboration with the national and local health authorities using the short form health survey (SF-12) for measuring and reporting on health related quality of life among the Danish adult population. The instrument has not, however, been validated in a Danish setting. The aim of this study was to assess the reliability and validity of the physical component summary (PCS) and the mental component summary (MCS) score of the 12-item short form health survey (SF-12) in a sample from Central Denmark Region. A total of 26,397 persons above the age of 25 were included in the analyses. Reliability was assessed by Cronbach’s α. The validity was assessed using known-groups comparisons and convergent validity. The factor structure was investigated through exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The Cronbach’s α showed high reliability with a score of 0.90 and 0.85 for PCS and MCS respectively. The SF-12 discriminated well with respect to gender, age, educational status and long term illness. Individual items correlated higher with own hypothesized scales than with other scales and summary measures corroborating the convergent validity. The EFA gave a two-factor structure. Irrespective of the chosen rotation method (varimax and oblimin) the items related to PCS loaded on one factor and the items related to MCS loaded on another factor. The factor structure was validated with acceptable model-fit values in CFA. The SF-12 instrument is a reliable and valid measure of health related quality of life among the population of Central Denmark Region.  相似文献   
940.

A survey is given of the use of modern statistical techniques in event history analysis, and in particular in the study of multi‐state life‐tables in demography. Emphasis is placed on the interplay between partial likelihood and nonparametric maximum likelihood based methods, a) when analysing semi‐Markov models or models with repeated spells, and b) in frailty models for inobservable heterogeneity.  相似文献   
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