共查询到10条相似文献,搜索用时 0 毫秒
1.
Mahdi Tavangar 《统计学通讯:理论与方法》2013,42(9):1347-1352
In recent years, several attempts have been made to characterize the generalized Pareto distribution (GPD) based on the properties of order statistics and record values. In the present article, we give a characterization result on GPD based on the spacing of generalized order statistics. 相似文献
2.
Let F and G be life distributions with respective failure rate functions rF and rG and respective 100α-percentile (0 < α < 1) residual life functions qα, F, and qα, G. Distribution-free two-sample tests are proposed for testing H0: F = G against H1,α,: qα, F ≥ qα, G and H2 α: qβ, F ≥ qβ,G for all β ≥ α. This class of tests includes as a special case the test of Kochar (1981) for the alternative H*2: rF ≤ rG. A theorem of Govindarajulu (1976) is extended in order to obtain asymptotic normality of the test statistics. The condition qα, F ≥ qα, G is implied by rF ≤ rG and is unrelated to the stochastic ordering F≤ G; if F and G are Weibull distributions with respective shape parameters c1 and c2 such that 1 ≤ C1 < C2, then qα,F ≥ qα, G for all α larger than a function of the parameters. 相似文献
3.
Often, in reliability theory, risk analysis, renewal processes and actuarial studies, mean residual life function or life expectancy plays an important role in studying the conditional tail measure of lifetime data. In this paper, we introduce the notion of the mean residual waiting time of records and present some monotonic and aging properties. Sharp bounds for the mean residual waiting time of records are also investigated. 相似文献
4.
An important marker for identifying the progression of human immunodeficiency virus (HIV) infection in an individual is the CD4 cell count. Antiretroviral therapy (ART) is a treatment for HIV/AIDS (AIDS, acquired immune-deficiency syndrome) which prolongs and improves the lives of patients by improving the CD4 cell count and strengthen the immune system. This strengthening of the immune system in terms of CD4 count, not only depends on various biological factors, but also other behavioral factors. Previous studies have shown the effect of CD4 count on the mortality, but nobody has attempted to study the factors which are likely to influence the improvement in CD4 count of patients diagnosed of AIDS and undergoing ART. In this paper, we use Poisson regression model (GPR) for exploring the effect of various socio-demographic covariates such as age, gender, geographical location, and drug usage on the improvement in the CD4 count of AIDS patients. However, if the CD4 count data suffers from under or overdispersion, we use GPR model and compare it with negative binomial distribution. Finally, the model is applied for the analysis of data on patients undergoing the ART in the Ram Manohar Lohia Hospital, Delhi, India. The data exhibited overdispersion and hence, GPR model provided the best fit. 相似文献
5.
Majid Asadl 《Statistical Papers》1998,39(4):347-360
LetX be a random variable andX
(w) be a weighted random variable corresponding toX. In this paper, we intend to characterize the Pearson system of distributions by a relationship between reliability measures
ofX andX
(w), for some weight functionw>0. 相似文献
6.
Mohammad Khanjari Sadegh 《统计学通讯:理论与方法》2013,42(4):475-480
This paper examines the relationships between the mean residual life functions of parallel and k-out-of-n systems with the regression of order statistics. Using these relationships, the results and properties about the mean residual life function of those systems can be used for the regression of order statistics and vice versa. Finally, the paper proposes a definition for the mean residual life function of a k-out-of-n system when the number of failed components of the system is known. 相似文献
7.
In this paper, we investigate the effect of a cold standby component on the mean residual life (MRL) of a system. When the system fails, a cold standby component is immediately put in operation. We particularly focus on the coherent systems in which, after putting the standby component into operation, the failure of the system is due to the next component failure. For these systems, we define MRL functions and obtain their explicit expressions. Also some stochastic ordering results are provided. Such systems include k-out-of-n systems. Hence, our results extend some results in literature. 相似文献
8.
Nezhat Shakeri 《统计学通讯:理论与方法》2013,42(5):777-790
Left censoring concept has been defined in different ways in statistical applications. Turnbull (1974) defines it in a particular way. Whereas in recent literature, especially in epidemiological studies, it has been defined in another way. This difference between the two approaches is the main reason that despite simplicity, Turnbull method cannot be applicable in all cases of doubly censored data. In this article we present a modified Turnbull method for analysis of doubly censored data adequate with recent definition. Comparison has been done with other statistical methods, including imputation estimator, full likelihood-based and conditional likelihood-based approach using Iranian HIV data. 相似文献
9.
Tests of fit for exponentiality based on a characterization via the mean residual life function 总被引:1,自引:1,他引:0
We study two new omnibus goodness of fit tests for exponentiality, each based on a characterization of the exponential distribution
via the mean residual life function. The limiting null distributions of the tests statistics are the same as the limiting
null distributions of the Kolmogorov-Smirnov and Cramér-von Mises statistics proposed when testing the simple hypothesis that
the distribution of the sample variables is uniform on the interval [0, 1].
Work supported by the Deutsche Forschungsgemeinschaft 相似文献
10.
Mohammad Khanjari Sadegh 《Journal of statistical planning and inference》2011,141(9):3267-3275
This article investigates some properties of the mean residual life function of (n−k+1)-out-of-n systems, when the lifetimes of the system components are independent random variables but not necessarily identically distributed and when the joint distribution of the component lifetimes is exchangeable, extending the results of Asadi and Goliforushani (2008) [On the mean residual life function of coherent systems. IEEE Transactions on Reliability 57 (4) 574-580] for the case of independent and identically distributed components. The extension to a coherent system with exchangeable components is also given. 相似文献