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Researchers have been developing various extensions and modified forms of the Weibull distribution to enhance its capability for modeling and fitting different data sets. In this note, we investigate the potential usefulness of the new modification to the standard Weibull distribution called odd Weibull distribution in income economic inequality studies. Some mathematical and statistical properties of this model are proposed. We obtain explicit expressions for the first incomplete moment, quantile function, Lorenz and Zenga curves and related inequality indices. In addition to the well-known stochastic order based on Lorenz curve, the stochastic order based on Zenga curve is considered. Since the new generalized Weibull distribution seems to be suitable to model wealth, financial, actuarial and especially income distributions, these findings are fundamental in the understanding of how parameter values are related to inequality. Also, the estimation of parameters by maximum likelihood and moment methods is discussed. Finally, this distribution has been fitted to United States and Austrian income data sets and has been found to fit remarkably well in compare with the other widely used income models. 相似文献
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In this paper, a new generalization of alpha-skew-normal distribution is considered. Some properties of this distribution, which is denoted by GASN(α, λ), including moments, maximum likelihood estimation of parameters, and some other properties are studied. Finally, using a real data set, we show that our new distribution is the best-fitted distribution for the used data among normal, skew normal, alpha-skew-normal, and skew-bimodal-normal distributions. 相似文献
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Mohammad Soleimani Simin Tavallaei Hossain Mansuorian Zahra Barati 《Social indicators research》2014,119(3):1589-1602
Quality of life (QoL) is being considered as one of the fundamental concepts in contemporary era. It tries to assess the level of general welfare of the communities. Urban transitional neighborhoods possess specific situation and as a result present distinctive QoL. The major objective of this study is to identify and measure the QoL dimensions in urban transitional neighborhoods using both objective and subjective indices pertaining to Darvazeshemiran neighborhood of Tehran. In order to accomplish this and gather needed data, 244 questionnaires were distributed among Darvazeshemiran’s residents. This study suggests that there exists low level of QoL in the study area. That is 64.3 % of the residents were dissatisfied with the prevailing level of QoL. This in turn is associated with the transitional nature of this neighborhood. The residents were strongly dissatisfied with regard to the environmental qualification as opposed to accessibility status. Furthermore, this study identified five objective factors respectively regarding QoL. There exists low correlation between subjective and objective dimensions. That demands simultaneous consideration of both objective and subjective dimensions. It is argued that individual treatments of each could not accurately represent the QoL of residents. 相似文献
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Zahra Mansourvar Torben Martinussen Thomas H. Scheike 《Scandinavian Journal of Statistics》2016,43(2):487-504
The mean residual life measures the expected remaining life of a subject who has survived up to a particular time. When survival time distribution is highly skewed or heavy tailed, the restricted mean residual life must be considered. In this paper, we propose an additive–multiplicative restricted mean residual life model to study the association between the restricted mean residual life function and potential regression covariates in the presence of right censoring. This model extends the proportional mean residual life model using an additive model as its covariate dependent baseline. For the suggested model, some covariate effects are allowed to be time‐varying. To estimate the model parameters, martingale estimating equations are developed, and the large sample properties of the resulting estimators are established. In addition, to assess the adequacy of the model, we investigate a goodness of fit test that is asymptotically justified. The proposed methodology is evaluated via simulation studies and further applied to a kidney cancer data set collected from a clinical trial. 相似文献
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Parisa Zarrin Zahra Khodadai Reinaldo B. Arellano-Valle 《Journal of Statistical Computation and Simulation》2019,89(1):38-51
The standard location and scale unrestricted (or unified) skew-normal (SUN) family studied by Arellano-Valle and Genton [On fundamental skew distributions. J Multivar Anal. 2005;96:93–116] and Arellano-Valle and Azzalini [On the unification of families of skew-normal distributions. Scand J Stat. 2006;33:561–574], allows the modelling of data which is symmetrically or asymmetrically distributed. The family has a number of advantages suitable for the analysis of stochastic processes such as Auto-Regressive Moving-Average (ARMA) models, including being closed under linear combinations, being able to satisfy the consistency condition of Kolmogorov’s theorem and providing the guarantee of the existence of such a SUN stochastic process. The family is able to be represented in a hierarchical form which can be used for the ease of simulation. In addition, it facilitates an EM-type algorithm to estimate the model parameters. The performances and suitability of the proposed model are demonstrated on simulations and using two real data sets in applications. 相似文献
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We introduce the problem of estimation of the parameters of a dynamically selected population in an infinite sequence of random variables and provide its application in the statistical inference based on record values from a non stationary scheme. We develop unbiased estimation of the parameters of the dynamically selected population and evaluate the risk of the estimators. We provide comparisons with natural estimators and obtain asymptotic results. Finally, we illustrate the applicability of the results using real data. 相似文献
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Most studies on the mobility of highly skilled migrants have been examined with a framework of global talent mobility and under conditions of neoliberal governance and economic globalization. In this study we challenge the notion of the hypermobile knowledge worker. Utilizing mixed methods, we examine the factors that attracted highly skilled migrants to Qatar and the conditions under which they might leave in the future. Rather than finding a group of footloose migrants attracted primarily to high-wage jobs, a lack of taxation or amenities, and with multiple alternative locations of residence, we find that highly skilled migrants exist on a spectrum of immobility. More significantly, this immobility depends on the migrant’s region of origin. For Asian and Western migrants immobility is attributed to the Kafala system or employer sponsorship, which hinders occupational and spatial mobility and ties workers to their sponsors. Arab highly skilled migrants are especially affected by lack of security and stability in their home countries, which makes these workers involuntarily immobile. The former group seem to be willing to accept a reduced level of agency and mobility for high income, whereas for the latter security and stability are more fundamental to their decision to come to Qatar. 相似文献
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In some applications of statistical quality control, quality of a process or a product is best characterized by a functional relationship between a response variable and one or more explanatory variables. This relationship is referred to as a profile. In certain cases, the quality of a process or a product is better described by a non-linear profile which does not follow a specific parametric model. In these circumstances, nonparametric approaches with greater flexibility in modeling the complicated profiles are adopted. In this research, the spline smoothing method is used to model a complicated non-linear profile and the Hotelling T2 control chart based on the spline coefficients is used to monitor the process. After receiving an out-of-control signal, a maximum likelihood estimator is employed for change point estimation. The simulation studies, which include both global and local shifts, provide appropriate evaluation of the performance of the proposed estimation and monitoring procedure. The results indicate that the proposed method detects large global shifts while it is very sensitive in detecting local shifts. 相似文献
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AbstractIn this paper we establish Kolmogrov–Feller weak law of large numbers for maximal weighted sums of i.i.d. random variables. 相似文献