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971.
    
This paper studies density estimation and regression analysis with data observed on a general unit hypersphere and contaminated by measurement errors. We establish novel density and regression estimators, and study their asymptotic properties such as the rates of convergence and asymptotic normality. We also provide two types of asymptotic confidence intervals for both density and regression functions. One type is based on the asymptotic normality of their estimators and the other type is based on the empirical likelihood technique. We present practical details on the implementation of our method as well as simulation studies and real data analysis.  相似文献   
972.
In this paper we introduce a flexible extension of the Gumbel distribution called the odd log-logistic exponentiated Gumbel distribution. The new model was implemented in GAMLSS package of R software and a brief tutorial on how to use this package is presented throughout the paper. We provide a comprehensive treatment of its general mathematical properties. Further, we propose a new extended regression model considering four regression structures. We discuss estimation methods based on censored and uncensored data. Two simulation studies are presented and four real data sets are applied to illustrating the usefulness of the new model.  相似文献   
973.
974.
排序集抽样下利用辅助变量中位数构建了总体均值的改进比率估计模型,分析了该比率估计量的偏差和均方误差,并与简单随机抽样下的比率估计比较,证明了改进后的比率估计均方误差更小。以农作物播种面积和产量为研究对象进行实例分析,研究表明,基于排序集样本和辅助变量中位数的比率估计方法可以有效提高估计精度,验证了该构造方法的可行性。  相似文献   
975.
Laplace Approximations for Natural Exponential Families with Cuts   总被引:1,自引:0,他引:1  
Standard and fully exponential form Laplace approximations to marginal densities are described and conditions under which these give exact answers are investigated. A general result is obtained and is subsequently applied in the case of natural exponential families with cuts, in order to derive the marginal posterior density of the mean parameter corresponding to the cut, the canonical parameter corresponding to the complement of the cut and transformations of these. Important cases of families for which a cut exists and the approximations are exact are presented as examples  相似文献   
976.
We study the asymptotic distribution of three‐step estimators of a finite‐dimensional parameter vector where the second step consists of one or more nonparametric regressions on a regressor that is estimated in the first step. The first‐step estimator is either parametric or nonparametric. Using Newey's (1994) path‐derivative method, we derive the contribution of the first‐step estimator to the influence function. In this derivation, it is important to account for the dual role that the first‐step estimator plays in the second‐step nonparametric regression, that is, that of conditioning variable and that of argument.  相似文献   
977.
Using the Vietnamese Living Standards Surveys for 2002, 2004, 2006 and 2008, we explore how provinces with differential access to trade liberalisation reforms differ in their pro-poor growth performance in Vietnam. Using both non-parametric and parametric estimation, we find strong, robust evidence of pro-poor growth in provinces with greater exposure to trade liberalisation. Using censored and uncensored regressions, the study also shows that increased wages play a critical role in this outcome. Our analysis enables identification of the core mechanisms through which the poor materialise their gains from trade-driven growth in a transition economy.  相似文献   
978.
Cities exist because of the productivity gains that arise from clustering production and workers, a process called agglomeration. How important is agglomeration for aggregate growth? This paper constructs a dynamic stochastic general equilibrium model of cities and uses it to estimate the effect of local agglomeration on aggregate growth. We combine aggregate time‐series and city‐level panel data to estimate the model's parameters via generalized method of moments. The estimates imply a statistically and economically significant impact of local agglomeration on the growth rate of per capita consumption, raising it by about 10%.  相似文献   
979.
甘肃省人口分布变化及其原因分析   总被引:3,自引:0,他引:3  
郭志仪  曹建云 《西北人口》2006,(3):13-15,19
本文从甘肃省人口的数量分布和自然密度着手,对人口分布的决定因素进行了分析,并结合耕地密度和人口综合经济密度状况对甘肃省人口分布的现状做出了评价,最后提出了引导人口在地区间合理分布的建议。  相似文献   
980.
We examine how trade openness influences income inequality within countries. The sample includes 139 countries over the period 1970–2014. We employ predicted openness as instrument to deal with the endogeneity of trade openness. The effect of trade openness on income inequality differs across countries. Trade openness tends to disproportionately benefit the relative income shares of the very poor, but not necessarily all poor, in emerging and developing economies. In most advanced economies, trade openness increased income inequality, an effect that is driven by outliers. Our results suggest a strong effect of trade openness on inequality in China and transition countries.  相似文献   
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