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1.
Hossein Nadeb Hamzeh Torabi 《Journal of Statistical Computation and Simulation》2019,89(10):1863-1876
In this paper, we consider inference of the stress-strength parameter, R, based on two independent Type-II censored samples from exponentiated Fréchet populations with different index parameters. The maximum likelihood and uniformly minimum variance unbiased estimators, exact and asymptotic confidence intervals and hypotheses testing for R are obtained. We conduct a Monte Carlo simulation study to evaluate the performance of these estimators and confidence intervals. Finally, two real data sets are analysed for illustrative purposes. 相似文献
2.
Mehdi Nakhodaeezadeh Mohammad Asghari Jafarabadi Hossein Matlabi Fatemeh Raeesi Dehkordi 《Journal of Housing for the Elderly》2017,31(3):272-285
In this cross-sectional study, we tested the relationship between sociophysical environment, quality of life (QOL), and perceived social support among elderly in Iran. The sample includes 128 participants recruited in the city of Shahrekord, Iran. We measured Evaluation of Older People Living Environment (EVOLVE); Control, Autonomy, Self-realization and Pleasure scale (CASP-19) and Multidimensional Scale of Perceived Social Support (MSPSS) tools respectively, through home-based observation and interview. A significant relationship was found between several domains of home environment, QOL, and perceived social support. The interaction effect of the home environment and gender in relation to QOL and perceived social support was statistically significant. Our results support that the home physical environment may not be considered a strong predictor of QOL among the Iranian elderly. 相似文献
3.
Cline Hoeks Hossein Azadi Parisa Rafiaani Khachak Enrique Troyo‐Dieguez Steven Van Passel Frank Witlox 《Development policy review : the journal of the Overseas Development Institute》2014,32(6):647-674
Given the historical development of land tenure in South Africa, the aim of this article is to examine the best routes to alleviate poverty and retain sustainable agriculture in the country. First, a theoretical framework is presented that relates land tenure to sustainability, and three historical periods (pre‐colonial, colonial, and apartheid) are then considered to explain the changes in land tenure and their consequences. The progress and main limitations of post‐apartheid land reform to approach agricultural sustainability and alleviate poverty are discussed. Based on the analysis, different possibilities for future land reform are elaborated, followed by some recommendations for future land‐reform policies in South Africa. 相似文献
4.
Effect of Sociocultural Context and Parenting Style on Scholastic Achievement among Iranian Adolescents 总被引:1,自引:0,他引:1
Seyed Mohammad Assadi Nayereh Zokaei Hossein Kaviani Mohammad Reza Mohammadi Padideh Ghaeli Mahmood Reza Gohari Fons J. R. van de Vijver 《Social Development》2007,16(1):169-180
School grades, family demographics and responses to the parental authority questionnaire were assessed in 240 eighth‐grade students in the southern, central and northern parts of Tehran, Iran's capital. The result showed that poorer families with traditional values had more authoritarian attitudes toward parenting than richer families with more modern values. In contrast to the studies conducted in East Asian societies, the current study found that authoritative parenting was the style associated with the highest academic outcome. Tests of mediation and moderation effects showed that the relation between parenting style and academic outcome was independent of sociocultural context. 相似文献
5.
Amal Saki Malehi Ebrahim Hajizadeh Kambiz A. Ahmadi Parvin Mansouri 《Journal of applied statistics》2015,42(9):1931-1945
In this paper, we will extend the joint model of longitudinal biomarker and recurrent event via copula function for accounting the dependence between the two processes. The general idea of joining separate processes by allowing model-specific random effect may come from different families distribution. It is a main advantage of the proposed method that a copula construction does not constrain the choice of marginal distributions of random effects. A maximum likelihood estimation with importance sampling technique as a simple and easy understanding method is employed to model inference. To evaluate and verify the validation of the proposed joint model, a bootstrapping method as a model-based resampling is developed. Our proposed joint model is also applied to pemphigus disease data for assessing the effect of biomarker trajectory on risk of recurrence. 相似文献
6.
Some statistics practitioners often ignore the underlying assumptions when analyzing a real data and employ the Nonlinear Least Squares (NLLS) method to estimate the parameters of a nonlinear model. In order to make reliable inferences about the parameters of a model, require that the underlying assumptions, especially the assumption that the errors are independent, are satisfied. However, in a real situation, we may encounter dependent error terms which prone to produce autocorrelated errors. A two-stage estimator (CTS) has been developed to remedy this problem. Nevertheless, it is now evident that the presence of outliers have an unduly effect on the least squares estimates. We expect that the CTS is also easily affected by outliers since it is based on the least squares estimator, which is not robust. In this article, we propose a Robust Two-Stage (RTS) procedure for the estimation of the nonlinear regression parameters in the situation where autocorrelated errors come together with the existence of outliers. The numerical example and simulation study signify that the RTS is more efficient than the NLLS and the CTS methods. 相似文献
7.
Simple nonparametric estimates of the conditional distribution of a response variable given a covariate are often useful for
data exploration purposes or to help with the specification or validation of a parametric or semi-parametric regression model.
In this paper we propose such an estimator in the case where the response variable is interval-censored and the covariate
is continuous. Our approach consists in adding weights that depend on the covariate value in the self-consistency equation
proposed by Turnbull (J R Stat Soc Ser B 38:290–295, 1976), which results in an estimator that is no more difficult to implement
than Turnbull’s estimator itself. We show the convergence of our algorithm and that our estimator reduces to the generalized
Kaplan–Meier estimator (Beran, Nonparametric regression with randomly censored survival data, 1981) when the data are either
complete or right-censored. We demonstrate by simulation that the estimator, bootstrap variance estimation and bandwidth selection
(by rule of thumb or cross-validation) all perform well in finite samples. We illustrate the method by applying it to a dataset
from a study on the incidence of HIV in a group of female sex workers from Kinshasa. 相似文献
8.
We examine how process choice links with design decisions about capital and human resources. Our analysis confirms empirically most expected differences between process- and product-focused plants for these decisions. What is unexpected is how top-performing plants resemble other plants within the same process choice category in most respects, while distinguishing themselves on a few selected process attributes. For example, better performing process-focused plants not only achieve higher machine flexibility levels and lower overhead costs as expected, but also have more intensive preventive maintenance programs. Similarly, product-focused plants that achieve certain hallmarks of process-focused plants also enjoy superior performance. 相似文献
9.
Atefeh Zamani Hossein Haghbin 《Journal of Statistical Computation and Simulation》2019,89(8):1423-1436
Functional time series is a popular method of forecasting in functional data analysis. The Box-Jenkins methodology for model building, with the aim of forecasting, includes three iterative steps of model identification, parameter estimation and diagnostic checking. Portmanteau tests are one of the most popular diagnostic checking tools. In particular, they are applied to find if the residuals of the fitted model are white noise. Gabrys and Kokoszka [Portmanteau test of independence for functional observations. J Am Stat Assoc. 2007;102(480):1338–1348.] proposed a portmanteau test of independence for functional observation based on Box and Pierce's statistic. Their statistic is too sensitive to the lag value, specially when the sample size is small. Here, two modifications of Gabrys and Kokoszka statistic are presented, which have superior properties in small samples. The efficiency of the modified statistics is demonstrated through a simulation study. 相似文献
10.