Horwitz's rule, transforming both sides and the design of experiments for mechanistic models

Summary. The paper develops methods for the design of experiments for mechanistic models when the response must be transformed to achieve symmetry and constant variance. The power transformation that is used is partially justified by a rule in analytical chemistry. Because of the nature of the relationship between the response and the mechanistic model, it is necessary to transform both sides of the model. Expressions are given for the parameter sensitivities in the transformed model and examples are given of optimum designs, not only for single-response models, but also for experiments in which multivariate responses are measured and for experiments in which the model is defined by a set of differential equations which cannot be solved analytically. The extension to designs for checking models is discussed.     

Graduate recruitment and the single European market

This article investigates changes in graduate recruitment strategies brought about by the Single European Market (SEM) in a sample of UK-based organisations, and compares them with approaches being adopted in France.French and British managers were surveyed on many aspects of graduate recruitment for the SEM, and both groups saw the likely impact of the SEM as significant. But there were differences by nationality: French companies were more active in recruiting graduates from other countries and their managers were more likely to believe that new skills, knowledge and attitudes would be required in the European graduates of the future. The results of this study have a number of implications for educational policy-makers as well as employers.     

The changing character of industrial relations: Comment

Readers wishing to correspond with Mr. O’Connell may do so through the editorial office of the Journal.     

Evaluating DISCOVER's Effectiveness in Enhancing College Students' Social Cognitive Career Development

College students (20 women, 14 men) seeking career counseling services at a university career center participated in this exploratory investigation. A 2 (DISCOVER treatment) × 2 (counseling treatment) research design was used to evaluate the individual and combined effects of DISCOVER (ACT, 1998) and counseling on participants' career decision‐making self‐efficacy and career decision‐making attributional style. Findings revealed a significant effect of the use of DISCOVER on participants' career decision‐making self‐efficacy and their sense of control over the career decision‐making process. Results are discussed regarding the implications for career counseling and ideas for further research in this domain.     

D-efficient window experimental designs

In the paper we present a new method of calculating sampling intervals, so-called windows, allowing an experimenter some flexibility in timing the sample collection, while a minimum required design efficiency for parameter estimation is assured. The method is based on the Equivalence Theorem for D-optimality what makes the length of each window related to the parameter sensitivities. An example of calculating the windows in a pharmacokinetic study is presented. Some other methods of calculating efficient sampling windows are briefly discussed.     

Age Cohort, Ancestry, and Immigrant Generation Influences in Family Relations and Psychological Well-Being among Black Caribbean Family Members

Immigration is contributing to the U.S. population becoming increasingly ethnically diverse. This article examines the role of family relations and well-being among different generations of Black Caribbean immigrants. Family disruptions, such as migration, can have complex effects on the support networks and emotional well-being of family members. Data from a recently completed national study of American Blacks in the United States, however, reveal significant similarities across ancestry and immigrant status in family contact, solidarity and well-being. It is concluded that intrafamilial relations may serve to overcome barriers of geographical distance in providing comparable levels of contact, solidarity, and well-being for both U.S.-born and immigrant Black Caribbean family members of different generations. Because of the increasing numbers of immigrant elders, these sources of family support will become increasingly more important in bridging the gaps between government resources and needed assistance in an aging society.     

Case study in the Bayesian analysis of a cost‐effectiveness trial in the evaluation of health care technologies: Depression

We present a case study based on a depression study that will illustrate the use of Bayesian statistics in the economic evaluation of cost‐effectiveness data, demonstrate the benefits of the Bayesian approach (whilst honestly recognizing any deficiencies) with respect to frequentist methods, and provide details of using the methods, including computer code where appropriate. Copyright © 2003 John Wiley & Sons, Ltd.