Abstract
Weibull mixtures have been used extensively in reliability and survival analysis, and they have also been generalized by allowing negative mixing weights, which arise naturally under the formation of some structures of reliability systems. These models provide flexible distributions for modeling dependent lifetimes from heterogeneous populations. In this paper, we study conditions on the mixing weights and the parameters of the Weibull components under which the considered generalized mixture is a well-defined distribution. Specially, we characterize the generalized mixture of two Weibull components. In addition, some reliability properties are established for these generalized two-component Weibull mixture models. One real data set is also analyzed for illustrating the usefulness of the studied model.
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Acknowledgments
The authors would like to thank two referees, the Associated Editor and the Editor-in-Chief for many constructive suggestions of an earlier version of this manuscript, which have improved the presentation of this paper. The authors are also thankful to Prof. J.G. Surles for providing the real data set. This work was partially supported by Fundación Séneca of the Regional Government of Murcia (Spain) under Grant 11886/PHCS/09.
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Franco, M., Balakrishnan, N., Kundu, D. et al. Generalized mixtures of Weibull components. TEST 23, 515–535 (2014). https://doi.org/10.1007/s11749-014-0362-x
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DOI: https://doi.org/10.1007/s11749-014-0362-x