http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Samawi, Hani M.,Helu, Amal,Rochani, Haresh D.,Yin, Jingjing,Linder, Daniel The Korean Statistical Society 2016 Communications for statistical applications and me Vol.23 No.5
The stress-strength models have been intensively investigated in the literature in regards of estimating the reliability ${\theta}$ = P(X > Y) using parametric and nonparametric approaches under different sampling schemes when X and Y are independent random variables. In this paper, we consider the problem of estimating ${\theta}$ when (X, Y) are dependent random variables with a bivariate underlying distribution. The empirical and kernel estimates of ${\theta}$ = P(X > Y), based on bivariate ranked set sampling (BVRSS) are considered, when (X, Y) are paired dependent continuous random variables. The estimators obtained are compared to their counterpart, bivariate simple random sampling (BVSRS), via the bias and mean square error (MSE). We demonstrate that the suggested estimators based on BVRSS are more efficient than those based on BVSRS. A simulation study is conducted to gain insight into the performance of the proposed estimators. A real data example is provided to illustrate the process.
Samawi, Hani M.,Al-Saleh, Mohammad F. The Korean Statistical Society 2002 Journal of the Korean Statistical Society Vol.31 No.4
Using some available information about the unknown variance $\sigma$$^2$ of a normal distribution with mean $\mu$, a sequential approach is used to estimate $\sigma$$^2$. Two cases have been considered regarding the mean $\mu$ being known or unknown. The mean square error (MSE) of the new estimators are compared to that of the usual estimator of $\sigma$$^2$, namely, the sample variance based on a sample of size equal to the expected sample size. Simulation results indicates that, the new estimator is more efficient than the usual estimator of $\sigma$$^2$whenever the actual value of $\sigma$$^2$ is not too far from the prior information.
On Quantifies Estimation Using Ranked Samples with Some Applications
Samawi, Hani-M. The Korean Statistical Society 2001 Journal of the Korean Statistical Society Vol.30 No.4
The asymptotic behavior and distribution for quantiles estimators using ranked samples are introduced. Applications of quantiles estimation on finding the normal ranges (2.5% and 97.5% percentiles) and the median of some medical characteristics and on finding the Hodges-Lehmann estimate are discussed. The conclusion of this study is, whenever perfect ranking is possible, the relative efficiency of quantiles estimation using ranked samples relative to SRS is high. This may translates to large savings in cost and time. Also, this conclusion holds even if the ranking is not perfect. Computer simulation results are given and real data from lows 65+ study is used to illustrate the method.
Valid estimation of odds ratio using two types of moving extreme ranked set sampling
Samawi, Hani M.,Al-Saleh, Mohammad Fraiwan 한국통계학회 2013 Journal of the Korean Statistical Society Vol.42 No.1
The paper provides estimation of the odds ratio between two independent groups using two types of Moving Extreme Ranked Set Sampling (MERSS). Theoretical properties of the suggested estimator are derived and compared with its counterpart estimator using simple random sampling (SRS). It is found that the estimator based on MERSS is always valid and has some advantages over that based on SRS. Real data from a level I Trauma center are used to illustrate the procedures developed in this paper.
Inference on Overlapping Coefficients in Two Exponential Populations Using Ranked Set Sampling
Samawi, Hani M.,Al-Saleh, Mohammad F. The Korean Statistical Society 2008 Communications for statistical applications and me Vol.15 No.2
We consider using ranked set sampling methods to draw inference about the three well-known measures of overlap, namely Matusita's measure $\rho$, Morisita's measure $\lambda$ and Weitzman's measure $\Delta$. Two exponential populations with different means are considered. Due to the difficulties of calculating the precision or the bias of the resulting estimators of overlap measures, because there are no closed-form exact formulas for their variances and their exact sampling distributions, Monte Carlo evaluations are used. Confidence intervals for those measures are also constructed via the bootstrap method and Taylor series approximation.
Perceptions and Preferences of Tourists Toward Selected Ecotourism Destinations in Bahrain
Habis Samawi,Yaser Najjar 세계문화관광학회 2008 Conference Proceedings Vol.9 No.0
The tourism industry has become one of the most considerable economic sectors in the world. Gulf countries, especially Bahrain included tourism as one of the most important exports that will help to diversify the country's GNP dependence on oil exporting only. However, little research has been done to highlight the driving factors of tourism and its impact on economic and cultural development. This paper is a behavioral oriented study that investigates and explains the perceptions and preferences of tourists toward selected tourism sites in Bahrain. It is structured in twofold: first, it presents the research approach and the selection of the analyzed sites; second, it presents the findings concerning tourists' demographic and socioeconomic characteristics, tourism participation rates, and perceptions toward tourism quality and levels of satisfaction. Data were collected by means of questionnaire interviews. 706 questionnaires were analyzed. Findings demonstrated the importance of the tourists' concerns in the planning process of tourism sites. The study also shows that variations in perceptions and participation rates resulted from variations in the socioeconomic characteristics of tourists.
Valid estimation of odds ratio using two types of moving extreme ranked set sampling
Hani M. Samawi,Mohammad Fraiwan AL-Saleh 한국통계학회 2013 Journal of the Korean Statistical Society Vol.42 No.1
The paper provides estimation of the odds ratio between two independent groups using two types of Moving Extreme Ranked Set Sampling (MERSS). Theoretical properties of the suggested estimator are derived and compared with its counterpart estimator using simple random sampling (SRS). It is found that the estimator based on MERSS is always valid and has some advantages over that based on SRS. Real data from a level I Trauma center are used to illustrate the procedures developed in this paper.
Jabrah, Rajai,Samawi, Hani M.,Vogel, Robert,Rochani, Haresh D.,Linder, Daniel F.,Klibert, Jeff The Korean Statistical Society 2017 Communications for statistical applications and me Vol.24 No.3
Drawing a sample can be costly or time consuming in some studies. However, it may be possible to rank the sampling units according to some baseline auxiliary covariates, which are easily obtainable, and/or cost efficient. Ranked set sampling (RSS) is a method to achieve this goal. In this paper, we propose a modified approach of the RSS method to allocate units into an experimental study that compares L groups. Computer simulation estimates the empirical nominal values and the empirical power values for the test procedure of comparing L different groups using modified RSS based on the regression approach in analysis of covariance (ANCOVA) models. A comparison to simple random sampling (SRS) is made to demonstrate efficiency. The results indicate that the required sample sizes for a given precision are smaller under RSS than under SRS. The modified RSS protocol was applied to an experimental study. The experimental study was designed to obtain a better understanding of the pathways by which positive experiences (i.e., goal completion) contribute to higher levels of happiness, well-being, and life satisfaction. The use of the RSS method resulted in a cost reduction associated with smaller sample size without losing the precision of the analysis.
Kernel density estimation based on progressive type-II censoring
Helu Amal,Samawi Hani,Rochani Haresh,Yin Jingjing,Vogel Robert 한국통계학회 2020 Journal of the Korean Statistical Society Vol.49 No.2
Progressive censoring is essential for researchers in industry as a mean to remove subjects before the final termination point in order to save time and reduce cost. Recently, kernel density estimation has been intensively investigated due to its asymptotic properties and applications. In this paper, we investigate the asymptotic properties of the kernel density estimators based on progressive type-II censoring and their application to hazard function estimation. A bias-adjusted kernel density estimator is also proposed. Our simulation indicates that the kernel density estimates under progressive type-II censoring is competitive compared with kernel density estimates under simple random sampling, depending on the censoring schemes. An example regarding failure times of aircraft windshields is used to illustrate the proposed methods.