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Stochastic comparisons of generalized mixtures and coherent systems

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Abstract

A distribution function \(F\) is a generalized mixture of the distribution functions \(F_1,\ldots ,F_k\) if \(F=w_1 F_1+\ldots +w_k F_k\), where \(w_1,\ldots ,w_k\) are some real numbers (weights) which should satisfy \(w_1+\ldots +w_k=1\). If all the weights are positive, then we have a classical finite mixture. If some weights are negative, then we have a negative mixture. Negative mixtures appear in different applied probability models (order statistics, estimators, coherent systems, etc.). The conditions to obtain stochastic comparisons of classical (positive) mixtures are well known in the literature. However, for negative mixtures, there are only results for the usual stochastic order. In this paper, conditions for hazard rate and likelihood ratio comparisons of generalized mixtures are obtained. These theoretical results are applied in this paper to study distribution-free comparisons of coherent systems using their representations as generalized mixtures. They can also be applied to other probability models in which the generalized mixtures appear.

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References

  • Agrawal A, Barlow RE (1984) A survey of network reliability and domination theory. Oper Res 32:478–492

    Article  MathSciNet  MATH  Google Scholar 

  • Baggs GE, Nagaraja HN (1996) Reliability properties of order statistics from bivariate exponential distributions. Commun Stat Theory Methods 12:611–631

    MathSciNet  MATH  Google Scholar 

  • Balakrishnan N, Cramer E (2008) Progressive censoring from heterogeneous distributions with applications to robustness. Ann Inst Stat Math 60:151–171

    Article  MathSciNet  MATH  Google Scholar 

  • Balakrishnan N, Cramer E (2014) The art of progressive censoring: applications to reliability and quality. Birkhäuser, New York

    Book  Google Scholar 

  • Balakrishnan N, Xie Q (2007a) Exact inference for a simple step-stress model with type-I hybrid censored data from the exponential distribution. J Stat Plan Inference 137:3268–3290

    Article  MathSciNet  MATH  Google Scholar 

  • Balakrishnan N, Xie Q (2007b) Exact inference for a simple step-stress model with type-II hybrid censored data from the exponential distribution. J Stat Plan Inference 137:2543–2563

    Article  MathSciNet  MATH  Google Scholar 

  • Balakrishnan N, Xie Q, Kundu D (2009) Exact inference for a simple step-stress model from the exponential distribution under time constraint. Ann Inst Stat Math 61:251–274

    Article  MathSciNet  MATH  Google Scholar 

  • Barlow RE, Proschan F (1975) Statistical theory of reliability and life testing. holt, rinehart and winston, New York

    MATH  Google Scholar 

  • Block HW, Li Y, Savits TH (2003) Initial and final behavior of failure rate functions for mixtures and systems. J Appl Probab 40:721–740

    Article  MathSciNet  MATH  Google Scholar 

  • Borgonovo E (2010) The reliability importance of components and prime implicants in coherent and non-coherent systems including total-order interactions. Eur J Oper Res 204:485–495

    Article  MATH  Google Scholar 

  • David HA, Nagaraja HN (2003) Order statistics, 3rd edn. Wiley, New York

    Book  MATH  Google Scholar 

  • Everitt BS, Hand DJ (1981) Finite mixture distributions. Chapman and Hall, New York

    Book  MATH  Google Scholar 

  • Franco M, Balakrishnan N, Kundu D, Vivo JM (2014) Generalized mixtures of weibull components. Test 23:515–535

    Article  MathSciNet  MATH  Google Scholar 

  • Glaser RE (1980) Bathtub and related failure rate characterizations. J Am Stat Assoc 75:667–672

    Article  MathSciNet  MATH  Google Scholar 

  • Kamps U, Cramer E (2001) On distributions of generalized order statistics. Statistics 35:269–280

    Article  MathSciNet  MATH  Google Scholar 

  • Kochar S, Mukerjee H, Samaniego FJ (1999) The “signature” of a coherent system and its application to comparison among systems. Naval Res Logist 46:507–523

    Article  MathSciNet  MATH  Google Scholar 

  • Kotz S, Balakrishnan N, Johnson NL (2000) Continuous multivariate distributions. Volume 1: models and applications. Wiley, New York

    Book  Google Scholar 

  • Navarro J (2008) Likelihood ratio ordering of order statistics, mixtures and systems. J Stat Plan Inference 138:1242–1257

    Article  MATH  Google Scholar 

  • Navarro J, Eryilmaz S (2007) Mean residual lifetimes of consecutive k-out-of-n systems. J App Probab 44:82–98

    Article  MathSciNet  MATH  Google Scholar 

  • Navarro J, Balakrishnan N, Samaniego FJ (2008a) Mixture representations of residual lifetimes of used systems. J Appl Probab 45:1097–1112

    Article  MathSciNet  MATH  Google Scholar 

  • Navarro J, Guillamon A, Ruiz MC (2009) Generalized mixtures in reliability modelling: applications to the construction of bathtub shaped hazard models and the study of systems. Appl Stoch Models Bus Ind 25:323–337

    Article  MathSciNet  MATH  Google Scholar 

  • Navarro J, Pellerey F, Di Crescenzo A (2015) Orderings of coherent systems with randomized dependent components. Eur J Oper Res 240:127–139

    Article  Google Scholar 

  • Navarro J, Rubio R (2010) Comparisons of coherent systems using stochastic precedence. Test 19:69–486

    Article  MathSciNet  Google Scholar 

  • Navarro J, Rubio R (2011) A note on necessary and sufficient conditions for ordering properties of coherent systems with exchangeable components. Naval Res Logist 58:478–489

    Article  MathSciNet  MATH  Google Scholar 

  • Navarro J, Rubio R (2012) Comparisons of coherent systems with non-identically distributed components. J Stat Plan Inference 142:1310–1319

    Article  MathSciNet  MATH  Google Scholar 

  • Navarro J, Ruiz JM, Sandoval CJ (2007) Properties of coherent systems with dependent components. Commun Stat Theory Methods 36:175–191

    Article  MathSciNet  MATH  Google Scholar 

  • Navarro J, Samaniego FJ, Balakrishnan N, Bhattacharya D (2008b) On the application and extension of system signatures in engineering reliability. Naval Res Logist 55:313–327

    Article  MathSciNet  MATH  Google Scholar 

  • Navarro J, Shaked M (2006) Hazard rate ordering of order statistics and systems. J Appl Probab 43:391–408

    Article  MathSciNet  MATH  Google Scholar 

  • Samaniego FJ (1985) On the IFR closure theorem. IEEE Trans Reliab 34:69–72

    Article  MATH  Google Scholar 

  • Samaniego FJ (2007) System signatures and their applications in engineering reliability. Springer, New York

    Book  MATH  Google Scholar 

  • Samaniego FJ, Navarro J (2016) On comparing coherent systems with heterogeneous components. Adv Appl Probab 48(1) (to appear)

  • Shaked M, Shanthikumar JG (2007) Stochastic orders, 2nd edn. Springer, New York

    Book  MATH  Google Scholar 

  • Wu JW (2001) Characterizations of generalized mixtures of geometric and exponential distributions based on upper record values. Stat Papers 42:123–133

    Article  MATH  Google Scholar 

  • Wu JW, Lee WC (1998) Characterization of generalized mixtures of exponential distribution based on conditional expectation of order statistics. J Jpn Stat Soc 28:39–44

    Article  MathSciNet  MATH  Google Scholar 

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Acknowledgments

I would like to thank the editors and the anonymous reviewers for several helpful suggestions. This research was supported in part by Ministerio de Economía y Competitividad under Grant MTM2012-34023-FEDER.

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Navarro, J. Stochastic comparisons of generalized mixtures and coherent systems. TEST 25, 150–169 (2016). https://doi.org/10.1007/s11749-015-0443-5

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