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1.
We study prevalence of son preference in families of East and South Asian origin living in the USA by investigating parental time investments in children using American Time Use Surveys. Estimates show that East and South Asian mothers spend an additional hour of quality time per day with their young (aged 0–2 years) sons than with young daughters; son preference in mothers’ time allocation declines as children get older. East and South Asian fathers’ time with young children is gender neutral. We find gender specialization in time with children aged 6–17 with fathers spending more time with sons and mothers spending more time with daughters. 相似文献
2.
Neeraj Misra 《统计学通讯:理论与方法》2018,47(19):4724-4740
In this paper, we consider a unified approach to stochastic comparisons of random vectors corresponding to two general multivariate mixture models. These stochastic comparisons are made with respect to multivariate hazard rate, reversed hazard rate and likelihood ratio orders. As an application, results are presented for stochastic comparisons of generalized multivariate frailty models. 相似文献
3.
The problem of constructing a confidence interval of ‘preassigned width and coverage probability’ considered by Costanza/ Hamdy and Son(1986) is further analyzed. Several multi-stage estimation procedures [ like, purely sequential, accelerated sequential and three-stage procedures ] are utilized to deal with the same estimation problem. The relative advantages and disadvantages of these procedures are discussed. 相似文献
4.
Neeldhara Misra Geevarghese Philip Venkatesh Raman Saket Saurabh Somnath Sikdar 《Journal of Combinatorial Optimization》2012,24(2):131-146
We study the recently introduced Connected Feedback Vertex Set (CFVS) problem from the view-point of parameterized algorithms. CFVS is the connected variant of the classical Feedback Vertex Set problem and is defined as follows: given a graph G=(V,E) and an integer k, decide whether there exists F?V, |F|??k, such that G[V?F] is a forest and G[F] is connected. We show that Connected Feedback Vertex Set can be solved in time O(2 O(k) n O(1)) on general graphs and in time $O(2^{O(\sqrt{k}\log k)}n^{O(1)})$ on graphs excluding a fixed graph H as a minor. Our result on general undirected graphs uses, as a subroutine, a parameterized algorithm for Group Steiner Tree, a well studied variant of Steiner Tree. We find the algorithm for Group Steiner Tree of independent interest and believe that it could be useful for obtaining parameterized algorithms for other connectivity problems. 相似文献
5.
Summary First-year mortality in rural Uttar Pradesh is characterized by a predominance (60 per cent) of deaths during the first month of life, of which 66 per cent are reported to be due to tetanus. This pattern is not typical of the historical experience of many developed countries and the current experience of some less developed countries where post-neo-natal mortality predominates. To examine this phenomenon, two causal models of neo-natal mortality (one for tetanus and one for all other diseases) are developed and tested using retrospective survey data from 2000 couples living in rural Uttar Pradesh. Neo-natal tetanus mortality is found to be primarily a function of opportunities for exposure to the disease (e.g. lack of antiseptic birth practices, ownership of large animals) rather than of socio-economic status or demographic variables. The importance of examining neo-natal mortality by cause, and the shortcomings inherent in making inferences from the historical experiences of Western nations are emphasized. 相似文献
6.
Using quadratic programming and utilizing the concept of ‘nearest proportional to size sampling design’, we propose a method for two-dimensional optimal controlled selection, which ensures zero probability to non-preferred samples. An alternative strategy for estimation of population total and variance is also suggested. The utility of the proposed procedure is demonstrated with the help of examples. 相似文献
7.
The problems of estimating the reliability function and Pr{X1+...+Xk ≤ Y} are considered. The random variables X’s and Y are assumed to follow binomial and Poisson distributions. Classical estimators
available in the literature are discussed and Bayes estimators are derived. In order to obtain the estimators of these parametric
functions, the basic role is played by the estimators of factorial moments of the two distributions. 相似文献
8.
First-year mortality in rural Uttar Pradesh is characterized by a predominance (60 per cent) of deaths during the first month of life, of which 66 per cent are reported to be due to tetanus. This pattern is not typical of the historical experience of many developed countries and the current experience of some less developed countries where post-neo-natal mortality predominates. To examine this phenomenon, two causal models of neo-natal mortality (one for tetanus and one for all other diseases) are developed and tested using retrospective survey data from 2000 couples living in rural Uttar Pradesh. Neo-natal tetanus mortality is found to be primarily a function of opportunities for exposure to the disease (e.g. lack of antiseptic birth practices, ownership of large animals) rather than of socio-economic status or demographic variables. The importance of examining neo-natal mortality by cause, and the shortcomings inherent in making inferences from the historical experiences of Western nations are emphasized. 相似文献
9.
Recently, there have been several reports from different parts of the World on the declining populations of the House Sparrow (Passer domesticus). In order to assess the population of this species in the National Capital Territory of Delhi-India, this study was conducted during June– August in 2007. Twenty-eight Fixed-Radius Point Count stations were established in five habitat types viz. High-density Urban Area, Medium-density Urban Area, Low-density Urban Area, Agriculture Area, and Forested Area, within the study area. The results show that the House Sparrow is still a dominant species in the agriculture area. However, its density is very low in the urban areas as compared to the other co-occurring common bird species viz. Rock Pigeon (Columba livia domestica), House Crow (Corvus splendens) and Common Myna (Acridotheres tristis). As, this study was conducted only over one season, the data is not sufficient to provide a clear picture of the population trend of the House Sparrow. Further studies are therefore required to investigate the relationship of the House Sparrow with other co-occurring common species, and to analyse the data on the type and quality of greenspaces and their relation with the House Sparrow in the study area. A long-term monitoring and conservation programme involving local people may be a good approach for maintaining the population of House Sparrow in the study area. 相似文献
10.
The problem of simultaneously selecting two non-empty subsets, SLand SU, of k populations which contain the lower extreme population (LEP) and the upper extreme population (UEP), respectively, is considered. Unknown parameters θ1,…,θkcharacterize the populations π1,…,πkand the populations associated with θ[1]=min θi. and θ[k]= max θi. are called the LEP and the UEP, respectively. It is assumed that the underlying distributions possess the monotone likelihood ratio property and that the prior distribution of θ= (θ1,…,θk) is exchangeable. The Bayes rule with respect to a general loss function is obtained. Bayes rule with respect to a semi-additive and non-negative loss function is also determined and it is shown that it is minimax and admissible. When the selected subsets are required to be disjoint, it shown that the Bayes rule with respect to a specific loss function can be obtained by comparing certain computable integrals, Application to normal distributions with unknown means θ1,…,θkand a common known variance is also considered. 相似文献