Estimating the structural dimension of regressions via parametric inverse regression

A new estimation method for the dimension of a regression at the outset of an analysis is proposed. A linear subspace spanned by projections of the regressor vector X , which contains part or all of the modelling information for the regression of a vector Y on X , and its dimension are estimated via the means of parametric inverse regression. Smooth parametric curves are fitted to the p inverse regressions via a multivariate linear model. No restrictions are placed on the distribution of the regressors. The estimate of the dimension of the regression is based on optimal estimation procedures. A simulation study shows the method to be more powerful than sliced inverse regression in some situations.     

Female-headed households in nonmetropolitan areas: Housing and demographic characteristics

This article describes selected demographic and housing characteristics of nonmetropolitan female-headed households. It compares nonmetropolitan female householders with the average U.S. household, including regional differences. Female heads are older and more likely to have members in poor health than U.S. households on average. Female heads are also more likely to be in poverty and to experience housing poverty. Although the female householders do not suffer from space and quality problems, housing affordability is a problem. Most female heads live in owned, single-family dwellings and are more likely to live in mobile homes than the average U.S. household. This research was funded under the auspices of the U.S. Department of Agriculture, Cooperative State Research Service, and the experiment stations in Idaho, Indiana (Purdue University), Iowa, Minnesota, Missouri, Nebraska, and New York (Cornell University). Also supporting the research were East Carolina University, Illinois State University, Kansas State University, and Western Michigan University. The authors thank Mary Ann Horvath and Roxanne Miller for their assistance in preparing the figures and document. She received her Ph.D. from Oklahoma State University. Her work includes research in housing and the economic well-being of women. She received her Ph.D. from The Ohio State University. Her research interests include housing and neighborhood assessment and women and public policy issues.     

Mixture and mixture–process variable experiments for pharmaceutical applications

Many experiments in research and development in the pharmaceutical industry involve mixture components. These are experiments in which the experimental factors are the ingredients of a mixture and the response variable is a function of the relative proportion of each ingredient, not its absolute amount. Thus the mixture ingredients cannot be varied independently. A common variation of the mixture experiment occurs when there are also one or more process factors that can be varied independently of each other and of the mixture components, leading to a mixture–process variable experiment. We discuss the design and analysis of these types of experiments, using tablet formulation as an example. Our objective is to encourage greater utilization of these techniques in pharmaceutical research and development. Copyright © 2004 John Wiley & Sons Ltd.     

Annual Review: Practice and Research in Career Counseling and Development, 1990

This review of the 1990 literature on career development and counseling emphasizes literature on career counseling approaches and interventions, and literature related to the general theme of “work within a life.” This theme addresses how work simultaneously expresses and influences how an individual functions as an integrated psychological being. The importance of the context of an individual's life is also emphasized throughout the review. Topics include race, sex, and multiple role issues, selected career choice issues and indecision, coping on the job, and job change and unemployment. Implications for career counseling are provided.     

“Paradigms lost”: Some thoughts on choosing methods in evaluation research

Patton agrees with us concerning the need for a catholic approach to method choices in evaluation. However, Patton criticizes us for setting up a straw man when we argued that quantitative and qualitative methods are not inevitably linked to different “paradigms” and that allegiance to a particular paradigm does not force the evaluator into a choice between mutually exclusive qualitative and quantitative methods. The first part of this article shows how some of the past literature creates the impression both of an inevitable method-paradigm linkage and of a forcedchoice between qualitative and quantitative paradigms. It is argued that such impressions could have pernicious consequences for evaluation practice by artificially restricting method choices. In the final section, we consider some of the difficulties of making method choices and suggest that the purposefully developed strengths of different methods should not be completely ignored.