The application of microcomputers in production management

The findings reported result from a questionnaire survey, and a number of company interviews. Further questions which need to be answered are identified, and a research project to provide these answers is outlined.     

Interspecies Extrapolation of Physiological Pharmacokinetic Parameter Distributions

Three methods (multiplicative, additive, and allometric) were developed to extrapolate physiological model parameter distributions across species, specifically from rats to humans. In the multiplicative approach, the rat model parameters are multiplied by the ratio of the mean values between humans and rats. Additive scaling of the distributions is denned by adding the difference between the average human value and the average rat value to each rat value. Finally, allometric scaling relies on established extrapolation relationships using power functions of body weight. A physiologically-based pharmacokinetic model was fitted independently to rat and human benzene disposition data. Human model parameters obtained by extrapolation and by fitting were used to predict the total bone marrow exposure to benzene and the quantity of metabolites produced in bone marrow. We found that extrapolations poorly predict the human data relative to the human model. In addition, the prediction performance depends largely on the quantity of interest. The extrapolated models underpredict bone marrow exposure to benzene relative to the human model. Yet, predictions of the quantity of metabolite produced in bone marrow are closer to the human model predictions. These results indicate that the multiplicative and allometric techniques were able to extrapolate the model parameter distributions, but also that rats do not provide a good kinetic model of benzene disposition in humans.     

Worker perceptions of procedural justice in workers’ compensation claims: Do unions make a difference?

The differences between union and nonunion workers’ perceptions of the fairness of the workers’ compensation claims process are examined. The hypothesis tested is that union members should perceive this process as more fair due to union “voice.” The data were collected in a survey of injured workers in Michigan who had filed a workers’ compensation claim. The empirical results indicate that unions have little impact on the perceived fairness of the claims process and that the main contribution of unions is the provision of a complaint mechanism. From the Bill of Rights to Chief Justice Earl Warren’s recurring inquiry of counsel, “but is it fair?” fair treatment has been treated as a value enforceable by law, standing at the very core of the constitutional, political, and social rights of the individual. —Westin and Feliu (1988, p. 255)     

Exploring the Michigan model: The relationship of personality, managerial support and organizational structure with health outcomes in entrants to the healthcare environment

Few studies have examined the role of managerial support in the adaptation of entrants to healthcare. The purpose of this study was to identify the job characteristic and role-related variables that mediate the effects of managerial support and personality on the mental and physical health and sickness absence in two independent groups of new recruits to a healthcare organization. Entrants to a healthcare environment (student nurses) were surveyed 25 weeks after entry. Latent variables represented neuroticism, demand, control, role clarity and affective outcome variables in a simplified version of the Michigan model of work stress (House, 1981). This study used a two-stage approach to structural equation modelling, exploring hypothesized structural models on an initial data set (N=195) prior to confirmation on an independent replication data set (N=239) using multi-sample methods. Finally the confirmed model of choice was evaluated using the combined data (N=434). Emotional distress reported at 6 months was found to be associated with dispositional characteristics of the entrant and indirectly, via job satisfaction, with managerial support from academic and clinical sources. Managerial support from academic and clinical sources had an indirect influence on job satisfaction, but by differing mechanisms involving role clarity and control. The demands perceived by the entrants arose from neuroticism and were independent of any other variable. Emotional distress had its deleterious association with sickness absence via somatic health. This study details a series of mechanisms that will subsequently be tested longitudinally.     

How bad will it be? Modelling the AIDS epidemic in Eastern Africa

The spread of HIV infection and the subsequent AIDS morbidity and mortality threatens to have a substantial impact on societies in subSaharan Africa. Infection levels are increasing rapidly in many regions, especially in urban areas. The consequences of high levels of infection are inescapable, although, due to the long incubation period, morbidity and mortality increases lag several years behind increases in infection levels. The impact of a serious AIDS epidemic will be felt by many sectors of the society. Mortality levels will substantially increase, especially among newborns and adults under age 50. This mortality will remove many productive members from the economy, while HIV-related illness will reduce the productivity of the infected population. Health care facilities will be severely strained to bear the increases in hospitalized populations. Those without access to the formal health care system will rely on family members for support and care.     

Baby talk to the babyfaced

The power of an infantile appearance to elicit baby talk was investigated by assessing the use of baby talk in task instructions to four-year-old children, who were portrayed as either relatively babyfaced or maturefaced. Men and women taught two tasks to a randomly selected boy or girl via a telephone conversation after being shown a photograph, which presumably depicted the child whom they were instructing. Paralleling facial differences between babies and adults, babyfaced children had rounder faces, larger eyes, thinner eyebrows, and smaller noses than the maturefaced. As predicted, adults used more baby talk when instructing babyfaced than maturefaced children. This effect was manifested in linguistic indicators of baby talk (slow timing and high clarification, simplification, and attention maintenance), as well as in paralinguistic indicators of baby talk (high pitch and changing intonation). The receipt of linguistic baby talk, in turn, facilitated the child's ability to choose a card which matched the one being described. The fact that facial babyishness influenced baby talk even when baby- and maturefaced children were equated in age, attractiveness, and perceived competence suggests that a small approximation to the craniofacial qualities that distinguish infants from adults may in and of itself be sufficient to elicit this speech register.This research was supported by NIMH grant #BSR5 R01 MH42684 to the first author. The authors would like to express their appreciation to the Brandeis University and Wellesley College Daycare Centers for their cooperation in this research. Thanks are also extended to Stacy Silberman for serving as one of the experimenters and to Becky Gilbert, Katina Lawdis, Sheryl Levy, and Liz Tighe for their help in coding the data.     

The development of a capacity for concern in antisocial children: Winnicott's concept of human relatedness

Winnicott's refreshing view of clinical practice includes the unique notion that delinquency is a sign of hope. Several of Winnicott's interpersonal concepts fit together to develop this thought: holding environment, capacity for concern, the use of the object, and hate in the counter transference. In this paper these four concepts are described and the case of a ten-year-old antisocial youngster is used to illustrate Winnicott's thinking and tie some of his illusive ideas into a difficult but familiar kind of practice situation. The therapeutic approach used was a mixture of case management and play therapy. What is different however is the way in which the therapist interpreted the youngster's behavior and stimulated his rich fantasy life.     

Some recent developments for regression analysis of multivariate failure time data

Cox's seminal 1972 paper on regression methods for possibly censored failure time data popularized the use of time to an event as a primary response in prospective studies. But one key assumption of this and other regression methods is that observations are independent of one another. In many problems, failure times are clustered into small groups where outcomes within a group are correlated. Examples include failure times for two eyes from one person or for members of the same family.This paper presents a survey of models for multivariate failure time data. Two distinct classes of models are considered: frailty and marginal models. In a frailty model, the correlation is assumed to derive from latent variables (frailties) common to observations from the same cluster. Regression models are formulated for the conditional failure time distribution given the frailties. Alternatively, marginal models describe the marginal failure time distribution of each response while separately modelling the association among responses from the same cluster.We focus on recent extensions of the proportional hazards model for multivariate failure time data. Model formulation, parameter interpretation and estimation procedures are considered.     

The impact of women's social position on fertility in developing countries

This paper examines ideas about possible ways in which the extent of women's autonomy, women's economic dependency, and other aspects of their position vis-à-vis men influence fertility in Third World populations. Women's position or status seems likely to be related to the supply of children because of its links with age at marriage. Women's position may also affect the demand for children and the costs of fertility regulation, though some connections suggested in the literature are implausible. The paper ends with suggestions for future research.