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41.
This paper addresses the problem of estimating a general parameter using information on an auxiliary variable X. We have suggested a class of exponential-type ratio estimators for the parameter and its properties are studied. It is identified that the estimators due to Upadhyaya et al. [Journal of Statistical Theory and Practice (2011), 5(2), 285–302] and Yadav and Kadilar [Revista Columbiana de Estadistica, (2013), 36(1), 145–152] are members of the proposed estimator. We have also shown that the suggested estimator is more efficient than the estimators of Upadhyaya et al. (2011 Upadhyaya, L.N., Singh, H.P., Chatterjee, S., Yadav, R. (2011). Improved ratio and product exponential type estimators. J. Stat. Theo. Pract. 5 (2): 285302.[Taylor &; Francis Online] [Google Scholar]) and Yadav and Kadilar (2013 Yadav, S.K., Kadilar, C. (2013). Improved exponential type ratio estimator of population variance. Revis. Colum. de Estadist. 36(1): 145152. [Google Scholar]). Numerical illustration is provided in support of the present study.  相似文献   
42.
The purpose of this study was to find the prevalence of low bone health conditions and assess associated nutritional and other risk factors in Indian women aged 41–60 years. A total of 1,911 women participated in this cross-sectional study. Bone health was assessed using an Omnisense multisite quantitative ultrasound bone densitometer on two sites (radius and tibia). Crude prevalence of osteopenia and osteoporosis was found to be 30.09% and 19.89%, respectively. The Indian women were deficient in a majority of nutrients. Postmenopause, hysterectomy, hyperthyroid, hypothyroid, hypertension, low physical activity, low sun exposure, high stress levels, and low calcium levels were found to be independent risk factors of low bone health.  相似文献   
43.
This paper captures the experiences of the faculty members of a relatively new graduate social work program situated in the largely rural state of Haryana India in reframing the foundation year practicum through community-based and engaged action learning in small villages. Located within Bhagat Phool Singh Vishwavidyalaya (BPSMV), north India's first all women public university, the mission of which is to enhance women's engagement in the greater society through post-secondary, professional and character education, the department is educating social workers for community engagement in social development and in the development of women as an empowered group in society, particularly at the village level. Over a three-year period, the faculty has successfully launched and sustained action learning as an alternative to the traditional practicum in social work education, enhanced civic engagement among students and faculty in three rural villages, and further developed community social work as a principal focus of social work education in India. The paper offers a rationale for action learning in the graduate social work curriculum, describes and documents the department's strategy of action learning, and lays out lessons learned from action learning as a central focus of pedagogy, research, and service within BPSMV Department of Social Work and the rural villages it serves.  相似文献   
44.
This paper explores the relations between older people, poverty and place in rural Britain. It develops previous work on rural poverty that has pointed both to the significance of older people within the rural poor population and to their denials of poverty. The paper also connects with recent discussions on the complexity of relations between poverty and social exclusion in later life, as well as key themes emerging from studies of older people in disadvantaged urban neighbourhoods. Drawing on findings from a survey of 4000 households in rural Wales and interviews with older people in poverty in three rural places, the paper provides a detailed examination of the materialities and experiences of poverty among older people in rural places. In particular, it highlights how older poor groups construct their lives in complex terms with references made to both social inclusions and exclusions. The research also points to the significance of the socio-cultural contexts of place in shaping older people's understandings of poverty in rural areas.  相似文献   
45.
Jackhammer manufacturers have recently developed lightweight (45-60 lbs) jackhammers intended to reduce the required lifting and pushing forces during operation. However, the vibration characteristics of the lightweight jackhammers and their effect on muscle activity are currently unknown. The objective of this study was to compare the measured vibration and muscle activity between: (i) conventional (90 lb) and light weight (60 lb) jackhammers, (ii) different pavement type/thickness combinations, and (iii) pneumatic and hydraulic jackhammers. Five jackhammers were tested on 4 and 6 inch thick asphalt and concrete pavements by four experienced operators. Analysis of the results revealed that both weight classes averaged 9.7 m/s(2) at the 20 Hz weighted 1/3 octave band frequency, and the TLV of daily exposure for either weight class of jackhammer was less than 1.5 hours/per day. There was an approximately 33% difference in vibration measured on the hand of the operators due to pavement thickness, 30% due pavement type, and no difference due to power source. Conventional jackhammers overall produced higher muscle activity than lightweight jackhammers. Although selection of the correct jackhammer for the job involves many factors including pavement type and thickness, the results of this research can be used to assist in selecting the appropriate jackhammer.  相似文献   
46.
We used data from the Birth to Twenty Cohort study to understand children’s receipt of financial support from their fathers in a low income, Black community in urban South Africa. Specifically, we (1) described fathers’ financial support over the life course of children; (2) estimated survival probabilities of receiving support for all children and not receiving support for children who experienced a parental union dissolution; and (3) identified factors that explained variation in the receipt of support after a union dissolution. Results suggest that most children received full or partial support throughout the life course. Furthermore, a high proportion of children received support after a union dissolution with much of the variation driven by pre-dissolution support, father’s education and the presence of extended kin.  相似文献   
47.
This article is a call to the field of counseling to bridge the research on trans and gender nonconforming (TGNC) youth identity development, family acceptance, and ally development to promote TGNC-affirming family, school, and community environments for TGNC youth. Opportunities and challenges counselors face in supporting ally development of families of TGNC youth are described. Interventions and strategies are described and recommendations for counselors working with the family members of TGNC youth are provided.  相似文献   
48.
49.
The purpose of this article is to introduce a new class of extended E(s2)-optimal two level supersaturated designs obtained by adding runs to an existing E(s2)-optimal two level supersaturated design. The extended design is a union of two optimal SSDs belonging to different classes. New lower bound to E(s2) has been obtained for the extended supersaturated designs. Some examples and a small catalogue of E(s2)-optimal SSDs are also included.  相似文献   
50.
MODEL-ASSISTED HIGHER-ORDER CALIBRATION OF ESTIMATORS OF VARIANCE   总被引:1,自引:0,他引:1  
In survey sampling, interest often centres on inference for the population total using information about an auxiliary variable. The variance of the estimator used plays a key role in such inference. This study develops a new set of higher‐order constraints for the calibration of estimators of variance for various estimators of the population total. The proposed strategy requires an appropriate model for describing the relationship between the response and auxiliary variable, and the variance of the auxiliary variable. It is therefore referred to as a model‐assisted approach. Several new estimators of variance, including the higher‐order calibration estimators of the variance of the ratio and regression estimators suggested by Singh, Horn & Yu and Sitter & Wu are special cases of the proposed technique. The paper presents and discusses the results of an empirical study to compare the performance of the proposed estimators and existing counterparts.  相似文献   
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