Nonparametric tests in small unbalanced samples: Application in employment-discrimination cases

Unbalanced-size samples arise naturally in equal-employment cases, as the minority fraction of all employees or applicants are invariably less than one half. Motivated by an actual case in which the median test with no power to detect disparate treatment was accepted in court, we develop a symmetrized form of the control median test having the same asymptotic properties as the median test. Since the actual case concerned the relative merits of the median and Wilcoxon test, a Monte Carlo study of the power of the new test and other nonparametric tests is reported. The results show that the new procedure is more powerful than the ordinary median test in small unbalanced samples. When the data come from a normal or double-exponential law, the Wilcoxon test is however usually superior to either of the others. When the data come from a Cauchy distribution, on the other hand, the powers of the procedures typically are reversed.     

Identifying influential observations in hierarchical cluster analysis

In a cluster analysis of a multivariate data set, it may happen that one or two observations have a disproportionately large effect on the analysis, in the sense that their removal causes a dramatic change to the results. It is important to be able to identify such influential observations, and the present paper addresses this problem. To do so, we must first quantify the effect of a single observation. Various definitions are discussed, and criteria for identifying influential observations are investigated; the minimum spanning tree and the number of neighbours of each observation are considered. The investigation concentrates on single-link cluster analysis, although complete-link analysis is also briefly discussed. Patterns emerge in both real and simulated data, which suggest ways of predicting observations with no effect and those with the greatest effect. It is not necessary to recalculate the results with each observation omitted—an economy of presentation as well as labour.     

Uncertainties in the Link Between Global Climate Change and Predicted Health Risks from Pollution: Hexachlorobenzene (HCB) Case Study Using a Fugacity Model

Industrial societies have altered the earth's environment in ways that could have important, long-term ecological, economic, and health implications. In this paper, we examine the extent to which uncertainty about global climate change could impact the precision of predictions of secondary outcomes such as health impacts of pollution. Using a model that links global climate change with predictions of chemical exposure and human health risk in the Western region of the United States of America (U.S.), we define parameter variabilities and uncertainties and we characterize the resulting outcome variance. As a case study, we consider the public health consequences from releases of hexachlorobenzene (HCB), a ubiquitous multimedia pollutant. By constructing a matrix that links global environmental change both directly and indirectly to potential human-health effects attributable to HCB released into air, soil, and water, we define critical parameter variances in the health risk estimation process. We employ a combined uncertainty/sensitivity analysis to investigate how HCB releases are affected by increasing atmospheric temperature and the accompanying climate alterations that are anticipated. We examine how such uncertainty impacts both the expected magnitude and calculational precision of potential human exposures and health effects. This assessment reveals that uncertain temperature increases of up to 5°C have little impact on either the magnitude or precision of the public-health consequences estimated under existing climate variations for HCB released into air and water in the Western region of the U.S.     

Higher Order Conditioning in the Newborn Rat: Effects of Temporal Disparity Imply Infantile Encoding of Simultaneous Events

Infant rats in the age range 8 to 16 days postnatal (P8–16) outperform older animals at learning an association between neutral olfactory stimuli, but only with simultaneous presentation of the odors; sequential presentation eliminates or reverses the infants' advantage. Such results suggest that infants and older animals differ in how they learn simultaneous events. This study tested whether the infant's special effectiveness with such learning is peculiar to P8–16 or is a general feature of infantile naïvete seen in newborns as well. At 3 hr of age newborn rats exhibited strikingly robust sensory preconditioning and second‐order conditioning, but only for simultaneous odors. Any degree of temporal disparity between odors (even 0 sec) eliminated sensory preconditioning and markedly reduced second‐order conditioning. This suggests that the weak differentiation among simultaneously presented stimuli in newborns may promote something similar to perceptual configuration.     

Self-reported distress, job dissatisfaction and the Type A behaviour pattern in a sample of full-time employed Australians

The Type A behaviour pattern (TABP), which relates to risk of coronary heart disease (CHD), has also been shown to relate to self-reported feelings of both psychological and physical distress, at least during those times when the TABP is activated by salient environmental circumstances. The importance of the occupational setting for those with the TABP has led to the speculation that such distress may arise, in part, from job dissatisfaction which comes about when the Type A individual is unable to exert sufficient control over the environment. Associations between the TABP and measures of job dissatisfaction have not, however, been widely reported. The present study examined associations between the TABP, job (dis)satisfaction and self-reported experiences of both psychological and physical distress in a sample of employed individuals, and found tentative evidence that the relationship between the TABP and distress was mediated in a modest way by self-perceived job (dis)satisfaction. The implications of this for the areas of work stress and occupational health are discussed.     

Possible causes of tax evasion

Only a limited number of empirical investigations, into possible causes of tax evasion, have been carried out. Most of these have been conducted since 1970 and they have been carried out in countries other than Australia. Much of the published research was reviewed lo develop a set of hypotheses which were then tested with Australian data. The results of those tests are reported in this article. It appears that several things might influence taxpayer's behaviour and in Australia, the exchange indicator could be one of the important influences.     

Pathological gambling and associated patterns of crime: Comparisons with alcohol and other drug addictions

The pattern of convictions for various categories of crime in the population of the United Kingdom was compared with the corresponding pattern in a sample of addictive gamblers drawn from Gamblers Anonymous in the U.K. A distinctive pattern of income-generating crime was found to be statistically associated with pathological gambling. This pattern was compared with other distinctive patterns associated with the intake of alcohol and with various other drugs and it was found to resemble most closely that of addiction to narcotic drugs.The possible role of gambling as a contributory cause of crime is discussed in the light of what is known of the issues surrounding other addictions as causes of their distinctive patterns of crime.The content and presentation of this paper benefited from the comments of J. Gillies and A.J. Weir, both of the Department of Psychology, University of Glasgow. The collection of the data would have been impossible without the active encouragement and assistance of the General Services Board of Gamblers Anonymous, U.K., its chairman G. Moody and the National Committee of Gamblers Anonymous, U.K.     

Organizational changes at a postal sorting terminal—their effects upon work satisfaction, psychosomatic complaints and sick leave

This paper describes a longitudinal study evaluating organizational changes at a postal sorting terminal in Sweden. One hundred postal workers were followed up for 1 year after the changes were put in place. Information about psychosocial factors, sleep disturbances and gastrointestinal complaints were collected by questionnaires administered at the onset of the changes and at 8 and 12 months later. Sick leave during the 1-year follow up was compared with that during the year before the changes were introduced. A significant increase in skill discretion and in authority over decisions occurred during the study period. The reported increase in skill discretion and authority over decisions correlated with a reduction in difficulties with sleep and with gastrointestinal complaints. Changes in reported contact with team mates and superiors also correlated with changes in the reporting of sleep difficulties and gastrointestinal complaints. There was a significant reduction in sick leave. The results indicate that the organizational changes improved the quality of work and at the same time reduced sick leave and psychosomatic complaints.     

Tempest-tost: Exile,ethnicity, and the politics of rescue

Refugees are individuals forced to flee from their homelands because of categorical persecution or because they are bystanders caught in the crossfire of war or civil strife. Such involuntary exile often leads to alienation in the most literal sense of the term. Whether expellees, escapees, or displaced persons, refugees share a common fate and, often, a common destiny: those who are dispossessed are dependent on others to provide care, succor, protection, and assistance. Yet responses to their plight are almost invariably highly selective, the quality of mercy being strained by considerations other than pure altruism. This paper, a commentary on the sociology of exile, attempts to convey the sense and significance of estrangement and responses to it in both historical and contemporary contexts. Early sections deal with concepts and concerns; later ones examine United States refugee policies and practices relating to exile, ethnicity, and the politics of rescue.Presidential address presented at the Eastern Sociological Society annual meeting, Arlington, Virginia, April 1992. Some parts of the address have appeared in different form in other publications by the author (see Rose, 1981, 1984, 1991).