Research ArticleOpen accessIn the abstractCritical Success Factors of Information Technology Outsourcing for Emerging MarketsSushil Paudel, Vinish KumarOutsourcing has gained popularity as several large U.S. companies in the 1980 s began delegating IT work to foreign firms. In outsourcing, one party (customer) asks another party (vendor) to do a particular job. Outsourcing has its own advantages, like reducing the cost and time and increasing performance and satisfaction. This study has focused on the critical success factors in … …Journal of Computer Science, Vol. 17, Issue 5 · 18 May 2021 · 8,126 accessesView PDFCite
Research ArticleOpen accessIn the abstractA New Family: Σh DistributionsYasser Mohamed Amer, Rania Mustafa ShalabiIn this study, a new method is proposed for generating families of the sum of the hazard functions for two distributions named the Σh distributions. This new family will help in the application of a wider range of life time data. Many new distributions, which are members of the family, are presented with emphasis on the Σh Exponential-Lomax distribution. Details … …Journal of Mathematics and Statistics, Vol. 17, Issue 1 · 7 Jan 2021 · 7,281 accessesView PDFCite
Research ArticleOpen accessIn the abstractEstimation and Reliability for a Special Type of Semi-Markov ProcessVlad Stefan Barbu, Alex Karagrigoriou, Andreas MakridesThis work deals with multi-state systems modelled by means of semi-Markov processes. The sojourn times are seen to be independent not identically distributed random variables and assumed to belong to one of two different general classes of distributions so that the first class is closed under maxima and the second one is closed under minima. We obtain maximum likelihood estimators … …Journal of Mathematics and Statistics, Vol. 15, Issue 1 · 20 Oct 2019 · 7,047 accessesView PDFCite
Research ArticleOpen accessIn the abstractStatistical Modeling of Temperature Extremes Behaviour in GhanaTwumasi-Ankrah Sampson, Nyantakyi Agyei KwadwoThis paper focuses on modeling the extreme maximum temperature in Ghana using the extreme value theory. This is to inform decision-makers to help them plan appropriate risk mitigating measures to reduce the damage caused by drought. The block maxima with Generalized Extreme Value (GEV) and the General Pareto (GP) (with “all excesses” and decluster peaks) were used on 113 years … …Journal of Mathematics and Statistics, Vol. 14, Issue 1 · 10 Jan 2019 · 7,117 accessesView PDFCite
Research ArticleOpen accessIn the abstractRisks Ratios of Shrinkage Estimators for the Multivariate Normal MeanAbdenour Hamdaoui, Nadia MezouarWe study the estimation of the mean θ of a multivariate Gaussian random variable X∼Np(θ,σ2Ip) in ℜp, σ2 is unknown and estimated by the chi-square variable S2∼σ2χn2. In this work we are interested in studying bounds and limits of risk ratios of shrinkage estimators to the maximum likelihood estimator X, when n and p tend to infinity. We recall that … …Journal of Mathematics and Statistics, Vol. 13, Issue 2 · 3 Apr 2017 · 7,108 accessesView PDFCite
Research ArticleOpen accessIn the abstractThe Uniform Truncated Negative Binomial Distribution and its PropertiesBahady I. Kamel, Shaban E. Abo Youssef, Mohamed G. SiefA new three parameters continuous distribution which is named the Uniform Truncated Negative Binomial (UTNB) distribution is introduced. It has the uniform and the Marshall-Olkin extended uniform distributions as sub-models. Some reliability and statistical properties of the new distribution are derived, including the shape behavior of the density and hazard rate functions, the mean residual life, moments and moment generating … …Journal of Mathematics and Statistics, Vol. 12, Issue 4 · 29 Nov 2016 · 7,308 accessesView PDFCite
Research ArticleOpen accessIn the abstractBurr-X Model Estimate using Bayesian and non-Bayesian ApproachesAbdullah Y. Al-HossainThe present paper is aimed at developing Bayesian and Maximum Likelihood estimations (ML) of the Burr type-X model of distribution when data are gathered from Type-II cumulative censoring with binomial eliminations. The procedures for getting the (ML) evaluations of the parameters are examined. The Bayes technique to get both point and interval estimators of the parameters are illustrated. The expected … …Journal of Mathematics and Statistics, Vol. 12, Issue 2 · 6 May 2016 · 7,210 accessesView PDFCite
Research ArticleOpen accessIn the abstractEstimation for Unknown Parameters of the Burr Type-XII Distribution Based on an Adaptive Progressive Type-II Censoring SchemeMontaser M. AmeinIn this study, the Maximum Likelihood Estimation (MLE) and Bayes estimation are exploited to make interval estimation based on adaptive progressive Type-II censoring for the Burr Type-XII distribution. Explicit form for the parameters of Bayes estimator doesn’t exist, so, Markov Chain Monte Carlo (MCMC) method is used as approximation to find posterior mean under squared error loss function. Real data … …Journal of Mathematics and Statistics, Vol. 12, Issue 2 · 29 Apr 2016 · 7,306 accessesView PDFCite
Research ArticleOpen accessIn the abstractProportional Hazard Inverse Weibull Distribution and Associated InferenceSuja M. Aboukhamseen, Mohamed E. Ghitany, Ramesh C. GuptaIn this study, we have considered the proportional hazard version of the inverse Weibull distribution. It has been shown that the density and hazard rate functions are unimodal and the mean residual life function is bathtub shaped. For the considered model, many functions of the parameters, such as the mean, variance, coefficient of variation and the critical points of the … …Journal of Mathematics and Statistics, Vol. 12, Issue 2 · 18 Apr 2016 · 7,385 accessesView PDFCite
Research ArticleOpen accessIn the abstractPOISSON-WEIGHTED EXPONENTIAL UNIVARIATE VERSION AND REGRESSION MODEL WITH APPLICATIONSHossein Zamani, Noriszura Ismail, Pouya FaroughiThis study introduces a new two-parameter mixed Poisson distribution, namely Poisson-Weighted Exponential (P-WE), which is obtained by mixing Poisson distribution with a new class of weighted exponential distribution. The new P-WE distribution provides a more flexible alternative for modelling over dispersed count data compared to Poisson distribution. The estimation procedures of P-WE distribution via method of moments and maximum likelihood … …Journal of Mathematics and Statistics, Vol. 10, Issue 2 · 8 Mar 2014 · 7,341 accessesView PDFCite