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161.
The author argues that it is clear that the manufacturers of most food products now have a bewildering array of alternative forms of packaging from which to choose. Due to pressure on profit margins, they will look for those systems that will be the cheapest having regard to many technical, commercial, legal and ecological factors. There will often be many different answers to any one packaging problem and all will be right to some extent! And not one is likely to satisfy every need!  相似文献   
162.
Let F(x) be a life distribution. An exact test is given for testing H0 F is exponential, versusH1Fε NBUE (NWUE); along with a table of critical values for n=5(l)80, and n=80(5)65. An asymptotic test is made available for large values of n, where the standardized normal table can be used for testing.  相似文献   
163.
We describe the summative assessment of role-play scenarios that we previously developed to teach central topics in the responsible conduct of research (RCR) to graduate students in science and engineering. Interviews with role-play participants, with participants in a case discussion training session, and with untrained students suggested that role-playing might promote a deeper appreciation of RCR by shifting the focus away from wanting to simply “know the rules.” We also present the results of a think-aloud case analysis study and describe the development of a behaviorally-anchored rating scale (BARS) to assess participants' case analysis performance.  相似文献   
164.
Some studies generate data that can be grouped into clusters in more than one way. Consider for instance a smoking prevention study in which responses on smoking status are collected over several years in a cohort of students from a number of different schools. This yields longitudinal data, also cross‐sectionaliy clustered in schools. The authors present a model for analyzing binary data of this type, combining generalized estimating equations and estimation of random effects to address the longitudinal and cross‐sectional dependence, respectively. The estimation procedure for this model is discussed, as are the results of a simulation study used to investigate the properties of its estimates. An illustration using data from a smoking prevention trial is given.  相似文献   
165.
To understand children's peer group affiliation, this study examined to what extent children in naturally occurring groups resemble each other on bullying, likeability, and perceived popularity. Participants were fourth‐ to sixth‐grade pupils (N = 461). Peer groups were identified using the social cognitive map procedure. Resemblance on bullying, likeability, and perceived popularity was evaluated by means of variance components models. Resemblance in peer groups was strongest for perceived popularity, followed by bullying and likeability. Moreover, resemblance on bullying could for a large part be attributed to the high‐perceived popularity of the group, and to a lesser extent, to the low likeability of the group. It is concluded that children showing bullying seem to affiliate with each other most of all to attain or maintain their position in a perceived popular peer group. Results stress the importance of considering the functionality of bullying from a group perspective.  相似文献   
166.
The investigation on the identification of outliers in linear regression models can be extended to those for circular regression case. In this paper, we propose a new numerical statistic called mean circular error to identify possible outliers in circular regression models by using a row deletion approach. Through intensive simulation studies, the cut-off points of the statistic are obtained and its power of performance investigated. It is found that the performance improves as the concentration parameter of circular residuals becomes larger or the sample size becomes smaller. As an illustration, the statistic is applied to a wind direction data set.  相似文献   
167.
The ecological patterns of suicide in metropolitan Sydney are described and policy recommendations made. Some inferences about the association of urbanization with suicide are suggested.  相似文献   
168.

In this paper our main objective is to investigate a deterministic inventory production lot-size model with a permissible delay in payment under a restriction. We analyse our deterministic inventory model under a restriction which will be assumed as the average inventory level. In fact we use in our analysis two approaches: the geometric programming approach; and the Lagrange method. Then a comparison between these two approaches is performed, which is our aim. Finally we deduce some previously published works of other researchers as special cases.  相似文献   
169.
What makes people perceive a leader as charismatic, and how do team leaders obtain performance outcomes from their followers? We examine leaders in times of organizational change and investigate the mechanisms through which leaders' change-promoting behaviors are associated with team performance. In a multilevel mediation model, we propose that the indirect relationship between change-promoting behaviors and team performance is sequentially transmitted through followers' perceptions of charisma and followers' commitment to change. A study of 33 leaders and 142 followers provides empirical support for the model, using multilevel structural equation modeling to analyze top-down relationships between leaders and followers and bottom-up relationships between followers and team outcomes. Results suggest that team leaders are perceived as more charismatic when they engage in change-promoting behaviors. These behaviors facilitate team performance through individual followers' perceived charisma and commitment to change.  相似文献   
170.
A general method for determining Pitman Nearness is given In the case of univariate estimators. This method is then applied to some estimation problems. The concept of Pitman Nearness is also generalized to the multivariate case. The James-Stein estimators are used to illustrate the multivariate comparison.  相似文献   
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