Ridge estimation of restricted parameters in production techniques

The problem of determining ridge estimates of the regression parameters in a two-input production function model,constrained to be non-negative,has been formulated as an exercise in quadratic programming. Relevant Kuhn-Tucker conditions have been derived and a small simulation studv has been carried out.     

Influence measure for the L1 regression

Because outliers and leverage observations unduly affect the least squares regression, the identification of influential observations is considered an important and integrai part of the analysis. However, very few techniques have been developed for the residual analysis and diagnostics for the minimum sum of absolute errors, L₁ regression. Although the L₁ regression is more resistant to the outliers than the least squares regression, it appears that outliers (leverage) in the predictor variables may affect it. In this paper, our objective is to develop an influence measure for the L₁ regression based on the likelihood displacement function. We illustrate the proposed influence measure with examples.     

Manpower planning for maintenance jobs in process industries

This paper describes a model for allocating the weekly requirement of manpower for maintenance jobs in the process units. We develop a simple procedure for the solution of the manpower allocation problem which has to deal with planned and unplanned jobs during a planning period. The solution procedure is illustrated by a numerical example. Possible extensions of this model are also discussed.     

Step-wise group screening with equal prior probabilities and no errors in observations

This paper introduces a screening procedure called step-wise group screening for isolating defective factors from a population consisting of defective (or important) and non-defective     

Is “humane managed care” an oxymoron? (Essay Review)

Abstract

Though the impact of managed care on clinical social work practice and education has been widely acknowledged and critiqued, Humane Managed Care? edited by Schamess and Lightburn, represents a compendium of papers addressing all aspects of the recent phenomena and its impact on practitioners, educators, and most especially our clients. In reviewing this impressive and comprehensive volume, this paper addresses many of the most controversial and painful aspects of the “Managed Care Revolution,” including its impact on the level of clinical practice and its economic and political ramifications. It is suggested that the editors and some of the authors are less hopeful about the possibility of providing “humane” treatment in the managed care environment than they were only a few years earlier, as indicated by a comparison of this volume with the 1996 special edition of Smith College Studies in Social Work. This article also critiques some of the anthology's chapters, which suggest that the changes in health care delivery will ultimately be beneficial to clinical social workers.

Essay Review: Humane Managed Care? Gerald Schamess, M.S.S. & Anita Lightburn, Ph.D. (Eds.). (Washington, DC: NASW Press, 1998.)     

Between two families: the social meaning of remittances for Vietnamese marriage migrants in Singapore

Scholars who have applied transnational perspectives to studies of migration and remittances have called for a move beyond the developmentalist approach to accommodate an expanded understanding of the social meanings of remittances. Researchers working in Asia have begun to view the remittances of money, gifts and services that labour migrants send to their families as transnational ‘acts of recognition’, as an enactment of gendered roles and identities, and as a component of the social practices that create the ties that bind migrants to their ‘home’ countries. In this article, we depart from the more common focus on remittance behaviour among labour migrants and turn instead to examine how, as marriage migrants, Vietnamese women generate and confer meaning on the remittances they send. First, from the women's viewpoint, we discuss the extent to which expectations vested in being able to generate remittances for the natal family by marrying a Singaporean man not only translate into motivation for marriage migration but also shape the parameters of the marriage. Second, we show how sending remittances are significant to the women as ‘acts of recognition’ in the construction of gendered identities as filial daughters, and, through the ‘connecting’ and ‘disconnecting’ power of remittances, in the reimagining of the transnational family. Third, we discuss the strategies that women devise in negotiating between the conflicting demands and expectations of their natal and marital families and in securing their ‘place’ between two families. We base our findings on an analysis of interviews and ethnographic work with Vietnamese women and their Singaporean husbands through commercial matchmaking agencies.     

Regression from another angle

This paper presents a simply viewed framework that brings together various concepts of regression, prediction, and principal components. Several new concepts related to prediction are introduced, and then the interrelationships of these concepts are established. The generalizations are examined in detail and are illustrated in the context of a well known data set.     

Skew-normal alpha-power model

In this paper, authors study properties and inference for the newly introduced skew-normal alpha-power model, generalizing both, the power-normal and skew-normal models. Inference is approached via maximum likelihood. Fisher information matrix is derived and shown to be nonsingular at the whole parametric space. Special emphasis is placed on the special case of the power–skew-normal model. Studies with real data illustrate the fact that the model can be very useful in applications, being able to overfit less general models entertained in the literature.     

Prediction intervals in exponential families

A method for obtaining prediction intervals for an outcome of a future experiment is presented. The method uses hypothesis testing as a tool to derive prediction intervals and assumes that the probability distributions of informative and future experiments are one parameter exponential families. Asymptotic similar mean coverage prediction intervals are derived using the score test as a test statistics. Examples are presented and asymptotic prediction limits are compared with the prediction limits given in the literature.