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71.
This study examines the influence of the socialization of aggression among different gender and social class groupings and the influence of psychosocial stage on cognitive developmental play preferences among groups of school aged children. Observations of 143 play groups were coded for play preference (symbolic play, practice play, games with rules) and play performance (cooperative or competitive). Findings of the log-linear data analysis suggest a middle class and masculine bias in Piaget's cognitive model (i.e., that as age increases children prefer more games with rules). This model held only for middle class and affluent boys. Girls (both latency and prepubertal) and lower socioeconomic groups tended to prefer practice play. Girls were more likely to play cooperatively; boys more likely to play competitively. Implications for theory development and clinical practice are explored.  相似文献   
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Although the health-enhancing effects of physical exercise have been well documented, less is known about how exercise benefits stressed employees psychologically. This article examines exercise as a coping response, and identifies changes in self-schemata (a person's underlying belief systems about him or herself) as the means by which exercise affects coping resources. In addition, by drawing on schema theory and the exercise literature, the active components of an exercise programme and the individuals who might enhance their ability to cope with stress through such a programme are identified.  相似文献   
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We propose some estimators of noncentrality parameters which improve upon usual unbiased estimators under quadratic loss. The distributions we consider are the noncentral chi-square and the noncentral F. However, we give more general results for the family of elliptically contoured distributions and propose a robust dominating estimator.  相似文献   
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Liberia has gone through civil crisis for over a decade which has resulted in the destruction of infrastructure and disruption of basic services delivery particularly in Monrovia, the capital city. Most of the 1.3 million people living in Monrovia are without adequate environmental sanitation and waste management services which situation poses a serious health risk to the residents. The current waste management service coverage is less than 20% and disposal is by indiscriminate open dumping. In 2003, there were series of outbreaks of cholera epidemics in the city during which time a total of 26,651 cases were reported with many dying.The waste management plan was initiated as an exit strategy of UNICEF following an intervention response programme to assist the Monrovia City Corporation (MCC) whose capacity in this area had been crippled as a result of years of war, through the provision of support in solid waste collection and disposal.The objectives of the plan were to:
(a) Improve waste management services delivery in the city.
(b) Strengthen the ability of the MCC to plan and manage the waste services delivery.
(c) Enhance cooperation of service beneficiaries through comprehensive and effective health education and service promotional campaign.
(d) Enhance revenue generation and community participation through the promotion of private sector and CBOs/NGOs active involvement in the waste management service delivery.
The general methodology adopted for the assignment entailed the following:Desk study and review of existing reports on Water and Environmental Sanitation (WES) in Monrovia and other relevant literature, consultation with stakeholders, site visits and participatory planning which aimed at soliciting the opinions of the various stakeholders involved with the respective components to capture their aspirations and experiences. It also covered collection and analysis of available information and data to facilitate the plan preparation and facilities design.The three-phased strategy (short, medium and long term) covering a period of 10 years (August 2004–December 2014), recommended a combination of technical options for collection based on the pursuit of staged development to allow for the adoption of realistically attainable standards within a framework of continuous and systematic improvements as economic conditions improved and new knowledge gained through practice. The plan sought to blend the capacity within the City Corporation with that of the private sector and NGOs/CBOs to respond to the diverse service demands of the city taking into consideration housing and infrastructural conditions, service costs and cost recovery to ensure sustainability. It also identified sources of financing and allocated financing responsibilities to facilitate effective plan implementation.  相似文献   
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Proportional reversed hazard rate model and its applications   总被引:1,自引:0,他引:1  
The purpose of this paper is to study the structure and properties of the proportional reversed hazard rate model (PRHRM) in contrast to the celebrated proportional hazard model (PHM). The monotonicity of the hazard rate and the reversed hazard rate of the model is investigated. Some criteria of aging are presented and the inheritance of the aging notions (of the base distribution) by the PRHRM is studied. Characterizations of the model involving Fisher information are presented and the statistical inference of the parameters is discussed. Finally, it is shown that several members of the proportional reversed hazard rate class have been found to be useful and flexible in real data analysis.  相似文献   
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