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991.
One of the most important challenges in health care management is balancing resources with fluctuating and uncertain demand. This study examines whether introducing a standardised process for sales and operations planning at a large university hospital improved specialty department managers’ knowledge of planning conditions and if so, whether decisions were made based on this knowledge. Using responses from a survey of 30 specialty department managers at Sahlgrenska University Hospital in Sweden, the analyses indicate that operational knowledge strengthens insights about the needs for strategic decisions, and vice versa. Moreover, knowledge is a necessary, but not sufficient, condition for making decisions at the department level. An overall planning and decision structure is required and should be implemented first at the hospital level to effectively allocate resources.  相似文献   
992.
This research examines how a firm's position in a coopetitive network (formed through cooperation among firms within an industry) influences the extent of the firm's competitive aggressiveness and market performance. The authors collected data on the competitive and cooperative actions of firms in the mobile telephone industry from 2000 to 2006, using structured content analysis of news reports. The results show that the centrality of a firm in a coopetitive network contributes to the firm's competitive aggressiveness through increased volume and variety of competitive actions. Further, the more central a firm is in the network, the greater is its market performance. Firms that undertake more volume and variety of competitive actions improve their market performance. Overall, these results show that being in a central position in a coopetition network is quite advantageous for the firm.  相似文献   
993.
Nonlinear mixed effects models (NLMEM) are used in pharmacokinetics to analyse concentrations of patients during drug development, particularly for pediatric studies. Approaches based on the Fisher information matrix can be used to optimize their design. Local design needs some a priori parameter values which might be difficult to guess. Therefore, two-stage adaptive designs are useful to provide some flexibility. We implemented in the R function PFIM the Fisher matrix for two-stage designs in NLMEM. We evaluated, with simulations, the impact of one-stage and two-stage designs on the precision of parameter estimation when the true and a priori parameters are different.  相似文献   
994.
W-graph refers to a general class of random graph models that can be seen as a random graph limit. It is characterized by both its graphon function and its motif frequencies. In this paper, relying on an existing variational Bayes algorithm for the stochastic block models (SBMs) along with the corresponding weights for model averaging, we derive an estimate of the graphon function as an average of SBMs with increasing number of blocks. In the same framework, we derive the variational posterior frequency of any motif. A simulation study and an illustration on a social network complete our work.  相似文献   
995.
Abstract

This column's offerings cover late spring through summer to fall of 2011: NISO Webinar: The Future of Integrated Library Systems: Part 1: RDA & Cataloging (May 11); American Library Association Annual Conference (June 23–28); Association of College and Research Libraries New England Serials and Electronic Resources Interest Group Summer Program: Current Trends in E-Journals (August 18); Kentucky Library Association/Kentucky School Media Association Joint Conference (September 28–October 1); American Society for Information Science and Technology Annual Meeting (October 9–12); Great Lakes E-Summit Conference (October 10–11); and Potomac Technical Processing Librarians Annual Meeting (October 21).  相似文献   
996.
When analysing a contingency table, it is often worth relating the probabilities that a given individual falls into different cells from a set of predictors. These conditional probabilities are usually estimated using appropriate regression techniques. In particular, in this paper, a semiparametric model is developed. Essentially, it is only assumed that the effect of the vector of covariates on the probabilities can entirely be captured by a single index, which is a linear combination of the initial covariates. The estimation is then twofold: the coefficients of the linear combination and the functions linking this index to the related conditional probabilities have to be estimated. Inspired by the estimation procedures already proposed in the literature for single-index regression models, four estimators of the index coefficients are proposed and compared, from a theoretical point-of-view, but also practically, with the aid of simulations. Estimation of the link functions is also addressed.  相似文献   
997.
In [H.W. Gómez, H.S. Salinas and H. Bolfarine, Generalized skew-normal models: Properties and inference, Statistics 40(6) (2006), pp. 495–505] introduces a new family of asymmetric distributions that depends on two parameters called, α and β, such as for the particular case β = 0 obtained skew-normal distribution. In this note we give a corrected version for the expression that is used in calculating the moments of such distribution.  相似文献   
998.
Conflict in a workgroup turns into harassment if a group member is persistently confronted with negative acts with few possibilities to retaliate. Cross-national differences in such intragroup harassment are considerable but wait to be understood. In this study, survey data from 44,836 employees in 44 countries revealed that a cultural in-group orientation was associated with lower employee harassment. In addition, and in agreement with Van de Vliert's climato-economic theory of culture, workforces reported more harassment in poorer countries with more demanding climates of colder-than-temperate winters, hotter-than-temperate summers, or both. Finally, it was found that the impact of climato-economic hardships on harassment suppressed the impact of cultural in-group orientation on harassment. Using the regression equation obtained for the sample of 44 countries, national levels of employee harassment for a broader pool of 103 countries were estimated and scrutinized for their validity for future research. Data from the World Values Surveys were used to validate the estimations. The results provide the basis for a further hypothesis, that employee harassment is more prevalent in countries with either survival or self-expression cultures than in countries with cultures that are intermediate between those two extremes. The results have implications for prevention and remedial measures.  相似文献   
999.
The methods presented in this article are based on the qualitative and quantitative analysis of close-out data drawn from a portfolio of 38 modification projects. The primary premise is that modification projects are intrinsically subject to quantity and complexity growth during the course of detailed engineering as a consequence of the indeterminate interface with the existing facility. The normative project control routines need to be supplemented by material take-offs-based weight monitoring as a basis for re-estimation and re-calibration of the project baselines as detailed engineering proceeds in order to mitigate this uncertainty as early as possible. Similarly, estimating needs to be based on norms drawn from performance measurement of modification work rather than extrapolations from greenfield projects, particularly the work performed on the platforms. This article presents a portfolio of project control methods based on the performance measurement principle covering the short term of single projects as well as the longer term multi-project perspective.  相似文献   
1000.
Abstract

In this study, the impact of psychosocial work characteristics on illness and work absenteeism has been examined. The study group consisted of 133 civil servants (33 men and 100 women) with a mean age of 43 years (range 21-65 years). Psychosocial work characteristics, social support, quality of life, work absenteeism, psychosomatic and gastrointestinal symptoms were assessed by means of questionnaires. Five different work support or functions were identified by factor analysis: appraisal support, belonging support, instrumental support, emotional support and supportive atmosphere. The analysis showed that work absenteeism was associated with lower belonging support and a less supportive atmosphere. Furthermore, psychosomatic symptoms were associated with lack of support at work, measured as belonging support, instrumental support and supportive atmosphere. Gastrointestinal symptoms were associated with lack of belonging support and lack of social integration outside work. A bad general health status was associated with lack of insrumental support. The association between work absenteeism and social support at work was confirmed in multivariate analysis with control for confounding factors. In this analysis, high work strain and low social support were associated with a lower quality of life, which in turn was associated with increased absenteeism. Although there are well-known difficulties in drawing causal conclusions from cross-sectional studies, it seems reasonable to conclude that social support at work is an important factor to take into consideration when analysing illness and absenteeism from work.  相似文献   
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