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961.
Michelle Maroto 《Journal of marriage and the family》2017,79(4):1041-1059
This study uses National Longitudinal Survey of Youth 1979 cohort data from 1994 through 2012 (N = 16,108 person‐years, 4,671 individuals) to investigate how coresidence with adult children influences asset levels among parents. It applies hybrid mixed effects regression models that partition between‐ and within‐person variation to estimate parental savings and financial assets over time and across different households. The results suggest that coresidence with adult children led to decreases in parental assets and savings. In the years in which their children lived at home, parents held 24% less in financial assets and 23% less in savings when compared with the years when adult children were not present. By expanding previous research that shows a relationship between increasing economic insecurity, limited wealth, and the rise in coresidence among young adults, this study also offers broader implications for the interconnectivity of financial hardship across generations. 相似文献
962.
Xiaoqiang Qian Ding Xu Hailong Liu Xiaoling Lin Yongjiang Yu Jian Kang 《The aging male》2017,20(4):250-256
Background: The etiology of benign prostatic hyperplasia (BPH) has not been well established. The preferred medical treatment for many men with symptomatic benign prostatic hyperplasia is either an α-adrenergic receptor antagonist (α-blocker), or a 5α-reductase inhibitor. Single nucleotide polymorphism (SNP) is a powerful tool for successful implementation of individualized treatment.Methods: Eighteen SNPs associated with drug efficacy in a Chinese population were genotyped in 790 BPH cases (330 aggressive and 460 non-aggressive BPH cases) and 1008 controls. All BPH patients were treated with α-adrenergic blockers for at least 9 months. We tested the associations between tagging single nucleotide polymorphism and BPH risk/aggressiveness, clinical characteristics at baseline, including the International Prostate Symptom Score (IPSS) and total prostate volume, and changes in clinical characteristics after treatment.Results: There were nine SNPs associated with BPH risk, clinical progression and therapeutic effect. (1) There were nine tSNPs been chosen in CYP3A4, CYP3A5 and RANBP3L genes. (2) The SNP, rs16902947 in RANBP3L at 5p13.2 (p?=?.01), was significantly associated with BPH. (3) We found two SNPs, rs16902947 in RANBP3L at 5p13.2 (p?=?.0388) and rs4646437 in CYP3A4 at 7q21.1 (p?=?.0325), associated with drug effect. (4) Allele “G” for rs16902947 was found to be risk alleles for BPH risk (OR=?2.357, 95%CI 1.01–1.48). The “A” allele of rs4646437 was associated with lower IPSS at baseline (β=??0.4232, p=?.03255).Conclusions: rs16902947, rs16902947 and rs4646437 single nucleotide polymorphisms are significantly associated with the clinical characteristics of benign prostatic hyperplasia and the efficacy of benign prostatic hyperplasia treatment. 相似文献
963.
964.
Indranil Ghosh N. Balakrishnan 《Journal of Statistical Computation and Simulation》2017,87(7):1467-1487
Income and wealth data are typically modelled by some variant of the classical Pareto distribution. Often, in practice, the observed data are truncated with respect to some unobserved covariate. In this paper, a hidden truncation formulation of this scenario is proposed and analysed. For this purpose, a bivariate Pareto (IV) distribution is assumed for the variable of interest and the unobserved covariate. Some important distributional properties of the resulting model as well as associated inferential methods are studied. An example is used finally to illustrate the results developed here. In this case, it is noted that hidden truncation on the left does not result in any new model, but the hidden truncation on the right does. The properties and fit of such a model pose a challenging problem and that is what is focused here in this work. 相似文献
965.
Expectiles were introduced by Newey and Powell in 1987 in the context of linear regression models. Recently, Bellini et al. revealed that expectiles can also be seen as reasonable law‐invariant risk measures. In this article, we show that the corresponding statistical functionals are continuous w.r.t. the 1‐weak topology and suitably functionally differentiable. By means of these regularity results, we can derive several properties such as consistency, asymptotic normality, bootstrap consistency and qualitative robustness of the corresponding estimators in nonparametric and parametric statistical models. 相似文献
966.
Accurate estimation of the parameters of superimposed sinusoidal signals is an important problem in digital signal processing and time series analysis. In this article, we propose a simultaneous estimation procedure for estimation of the number of signals and signal parameters. The proposed sequential method is based on a robust bivariate M-periodogram and uses the orthogonal structure of the superimposed sinusoidal model for sequential estimation. Extensive simulations and data analysis show that the proposed method has a high degree of frequency resolution capability and can provide robust and efficient estimates of the number of signals and signal parameters. 相似文献
967.
Li-Fei Huang 《统计学通讯:模拟与计算》2017,46(7):5763-5771
The ordinary Wilcoxon signed rank test table provides confidence intervals for the median of one population. Adjusted Wilcoxon signed rank test tables which can provide confidence intervals for the median and the 10th percentile of one population are created in this paper. Base-(n + 1) number system and theorems about property of symmetry of the adjusted Wilcoxon signed rank test statistic are derived for programming. Theorem 1 states that the adjusted Wilcoxon signed rank test statistic are symmetric around n(n + 1)/4. Theorem 2 states that the adjusted Wilcoxon signed rank test statistic with the same number of negative ranks m are symmetric around m(n+1)/2. 87.5% and 85% confidence intervals of the median are given in the table for n = 12, 13,…, 29 to create approximated 95% confidence intervals of the ratio of medians for two independent populations. 95% and 92.5% confidence intervals of the 10th percentile are given in the table for n = 26, 27, 28, 29 to create approximated 95% confidence regions of the ratio of the 10th percentiles for two independent populations. Finally two large datasets from wood industry will be partitioned to verify the correctness of adjusted Wilcoxon signed rank test tables for small samples. 相似文献
968.
In this paper, we introduce a new positive dependence concept between two non negative random variables which is related to a conditional version of the mean inactivity time order. A number of properties and relationship between the new notion and the concept of positive likelihood ratio dependence (PLRD) is discussed. Some results in terms of proposed notions for the Archimedean family of copulas are provided. 相似文献
969.
970.
We propose a new adjustment for constructing an improved version of the Wald interval for linear combinations of binomial proportions, which addresses the presence of extremal samples. A comparative simulation study was carried out to investigate the performance of this new variant with respect to the exact coverage probability, expected interval length, and mesial and distal noncoverage probabilities. Additionally, we discuss the application of a criterion for interpreting interval location in the case of small samples and/or in situations in which extremal observations exist. The confidence intervals obtained from the new variant performed better for some evaluation measures. 相似文献