Work orders: Analysing employment histories using sequence data

The analysis of employment histories has been facilitated recently by advances in survey methodology, statistical processes and computing power. While much work has focused on transitions between states and time spent in one state, the potential of analysing a series of states (i.e. careers) has largely been ignored. A concentration on movement between two states, whilst allowing relevant contextual covariates to be controlled for, often ignores valuable data both prior to and after the episode in question. Analysis of extended sequences of employment states is better able to describe employment trajectories. Furthermore, comparison of sequences permits either allocation to theoretical categories, or the identification of latent groupings using cluster analysis. The resulting typology of careers can then be used in inferentially based analyses. This paper explores sequence analysis using Optimal Matching Analysis (OMA). OMA is explained in relation to one broad substantive issue: the relationship between employment trajectories and gender.     

A method for combining inference across related nonparametric Bayesian models

Summary.  We consider the problem of combining inference in related nonparametric Bayes models. Analogous to parametric hierarchical models, the hierarchical extension formalizes borrowing strength across the related submodels. In the nonparametric context, modelling is complicated by the fact that the random quantities over which we define the hierarchy are infinite dimensional. We discuss a formal definition of such a hierarchical model. The approach includes a regression at the level of the nonparametric model. For the special case of Dirichlet process mixtures, we develop a Markov chain Monte Carlo scheme to allow efficient implementation of full posterior inference in the given model.     

Use of generalized estimating equations in a trial in influenza to explore treatment effects over time

For trials with repeated measurements of outcome, analyses often focus on univariate outcomes, such as analysis of summary measures or of the last on‐treatment observation. Methods which model the whole data set provide a rich source of approaches to analysis. For continuous data, mixed‐effect modelling is increasingly used. For binary and categorical data, models based on use of generalized estimating equations account for intra‐subject correlation and allow exploration of the time course of response, as well as providing a useful way to account for missing data, when such data can be maintained as missing in the analysis. The utility of this approach is illustrated by an example from a trial in influenza. Copyright © 2004 John Wiley & Sons Ltd.     

Information technology: The threat to unions

Conclusions Although seldom recognized in the flurry of enthusiastic support, information technology has a dark side for unions. The Internet and the Web, with its power and convenience magnified by wireless communication, will reduce the relevancy of the traditional workplace-centered appeals of organizing unions. With greater physical distance and less psychological attachment to their employer and workplace, professional, clerical, technical, and sales workers will believe that collective bargaining does not fit their situations. Organizing these workers will require that unions not only have to broaden their mode of representation, perhaps even reviving associate membership, but also compete against advocacy and identity organizations. To make matters even worse, when unions try to organize any group of workers regardless of whether or not their jobs have been transformed by information technology, and when unions try to maintain their influence in already organized workplaces, they will have to compete against employer-controlled intranets.     

管理供应商的成功要诀

若供应商不按时交货怎么办?若质量马虎,又该怎么办?随着外包业务的不断增长,越来越多的业务人员有责任维系与供应商的关系。但是,若供应商不按时交货怎么办?若质量马虎．又该怎么办?在以往．经理人解决此类麻烦的办法是:试图在合约中考虑到每种可能的意外情况,一旦事与愿违,便威胁退出合作。但现在,这些办法都不能完全奏效。在如今日新月异的市场变化中,拟     

Attitudes Toward Younger and Older Adults: An Updated Meta-Analytic Review

This meta-analytic review of 232 effect sizes showed that, across five categories, attitudes were more negative toward older than younger adults. Perceived age differences were largest for age stereotypes and smallest for evaluations. As predicted by social role theory ( Eagly, 1987 ), effect sizes were reduced when detailed information was provided about the person being rated. The double standard of aging emerged for evaluations and behavior/behavioral intentions, but was reversed for the competence category. Perceptions depended on respondent age also. Results demonstrated both the multi-dimensionality and the complexity of attitudes toward older adults ( Hummert, 1999 ; Kite & Wagner, 2002 ).     

Options traders exhibit subadditive decision weights

Professional options traders priced risky prospects as well as uncertain prospects whose outcomes depended on future values of various stocks. The prices of the risky prospects coincided with their expected value, but the prices of the uncertain prospects violated expected utility theory. An event had greater impact on prices when it turned an impossibility into a possibility or a possibility into a certainty than when it merely made a possibility more or less likely, as predicted by prospect theory. This phenomenon is attributed to the subadditivity of judged probabilities.