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991.
Aggressive driving is acknowledged as a contributor to motor vehicle crashes. This study explored a theoretical model of aggressive expression and crash‐related outcomes using self‐report data collected, using an online questionnaire, from drivers in the United Kingdom and the Republic of Ireland. The proposed model tested whether the personality traits of boredom proneness, sensation seeking, and impulsivity, coupled with trait driving anger, predicted aggressive driving; and whether aggressive driving predicted crash‐related outcomes (loss of concentration and control, near misses, and moving violations). The structural model was confirmed, with aggressive expressions of anger being found to mediate the relationships driving anger and impulsivity had with the crash‐related outcomes. Multigroup invariance analysis showed that the model remained invariant across drivers from the United Kingdom and Ireland, suggesting that the contributing factors for aggressive expression and crash involvement are similar across both countries. When self‐reported crash‐related conditions were compared between drivers in the United Kingdom and Ireland, drivers in the United Kingdom reported more aggressive driving, more minor crashes, more incidents of road rage, and more frequent losses of concentration and vehicle control.  相似文献   
992.
We examined the UK's effectiveness in reducing Child Mortality with 20 other Western countries, in the context of their national health expenditures, and, relative poverty — measured by ‘Income Inequality’ the gap between top and bottom 20 per cent of income. W.H.O. Child (0–14) Mortality Rates (CMR) and GDP Expenditure on Health (% GDPHE) were examined and a cost‐effectiveness ratio calculated, which is the reduced CMR over the period divided by average GDPHE. The highest average % GDPHE was USA at 13.2 per cent; the UK's 7.3 per cent was equal lowest. The widest Income Inequality was USA 8.5 times; the UK at 7.2 was third widest. The highest CMR was the USA 2436 per million (pm), the UK's 1630 pm, although representing a fall of 62 per cent was fourth highest. However, UK cost‐effectiveness ratio (1: 350) was eighth best of 21 countries. Only Income Inequality correlated significantly with CMR. UK CMR fell significantly more than five countries but ten others declined more. If UK deaths had been at the average of the 17 countries with lower CMR, there would have been 1827 fewer deaths. British children's poverty and health expenditure means they and their services are doubly disadvantaged although the NHS relatively achieved more with comparatively less.  相似文献   
993.
In acute toxicity testing, organisms are continuously exposed to progressively increasing concentrations of a chemical and deaths of test organisms are recorded at several selected times. The results of the test are traditionally summarized by a dose-response curve, and the time course of effect is usually ignored for lack of a suitable model. A model which integrates the combined effects of dose and exposure duration on response is derived from the biological mechanisms of aquatic toxicity, and a statistically efficient approach for estimating acute toxicity by fitting the proposed model is developed in this paper. The proposed procedure has been computerized as software and a typical data set is used to illustrate the theory and procedure. The new statistical technique is also tested by a data base of a variety of chemical and fish species.  相似文献   
994.
Abstract This paper assesses the effects of the community sex ratio on black family formation and family structure in nonmetropolitan parishes in Louisiana. As predicted, the sex ratio is found to have strong positive effects on marriage prevalence for black women, the prevalence of husband and wife families for black families, and the percentage of black children residing in husband and wife families and strong negative effects on the nonmarital fertility ratio for black women. Thus, we conclude that the sex ratio hypothesis should be given greater prominence in discussions of changes in black family structure and that sex ratio effects should be taken into account when framing policies aimed at ameliorating social problems attendant to high relative incidence of nonmarital births and single-parent, female-headed families with young children (e.g., poverty). We also note that, while the literature overwhelmingly concentrates on black family structure in urban areas, changes in the black family are equally pronounced in nonmetropolitan areas suggesting that explanations emphasizing the dynamics of urban ghettos may be too narrow.  相似文献   
995.

Michael (1985) distinguished between two types of verbal behavior: topography-based and stimulus selection-based verbal behavior. The current research was designed to empirically examine these two types of verbal behavior while addressing the frequently debated question, Which augmentative communication system should be used with the nonverbal developmentally disabled person? Four mentally retarded adults served as subjects. Each subject was taught to tact an object by either pointing to its corresponding symbol (selection-based verbal behavior), or making the corresponding sign (topography-based verbal behavior). They were then taught an intraverbal relation, and were tested for the emergence of stimulus equivalence relations. The results showed that signed responses were acquired more readily than pointing responses as measured by the acquisition of tacts and intraverbals, and the formation of equivalence classes. These results support Michael’s (1985) analysis, and have important implications for the design of language intervention programs for the developmentally disabled.

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Occupational influences on retirement,disability, and death   总被引:4,自引:1,他引:3  
This research examines the alternative mechanisms by which occupations influence the nature and timing of older men's labor force withdrawal. We specifically assess the extent to which occupational factors operate directly and indirectly on exiting events and whether occupations constrain traditional determinants of labor force participation. Based on a discrete-time hazard modeling approach, the results substantiate that the occupational task activities--substantive complexity and physical demands--are key elements of the work environment that are evaluated against nonwork alternatives. In the case of retirement, these aspects of occupational attractiveness function as a dominant and direct force in retirement decision making. With regard to disability, the occupational attribute of substantive complexity operates as an indirect advantage (through higher wages) by reducing the risk of disability. Indicators of career continuity also influence retirement among older workers. Finally, the results suggest that financial characteristics and health problems are central to the distribution of older workers across the alternative destination statuses of retirement, disability, and death.  相似文献   
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