Abstract
In this paper a general procedure is proposed to get stochastic comparisons of residual lifetimes of coherent systems. The comparison results obtained are based on the structure of the system and on properties of the copula used to describe the dependence between the component lifetimes. They are distribution-free with respect to the component lifetime distributions. We consider two system residual lifetimes at a given time \(t>0\). In the first one, we just assume that the system is working at time t while, in the second one, we assume that all the components are working at time t. We study the main stochastic orderings: hazard rate, stochastic, mean residual life and likelihood ratio orders. Specific results are obtained in the particular case of independent components and in the case of identically distributed components. Some illustrative examples are included. They prove that, in some cases, these system residual lifetimes are not ordered. Even more, surprisingly, sometimes the first residual lifetime is greater (in some stochastic sense) than the second one under a given dependence model.
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References
Asadi M, Bayramoglu I (2006) The mean residual life function of a \(k\)-out-of-\(n\) structure at the system level. IEEE Trans Reliab 55:314–318
Barlow RE, Proschan F (1975) Statistical theory of reliability and life testing, probability models, international series in decision processes, series in quantitative methods for decision making. Holt, Rinehart and Winston, Inc., New York/Montreal
Durante F, Sempi C (2015) Principles of copula theory. CRC/Chapman & Hall, London
Eryilmaz S (2013) On residual lifetime of coherent systems after the rth failure. Stat Pap 54:243–250
Gupta N, Misra N, Kumar S (2015) Stochastic comparisons of residual lifetimes and inactivity times of coherent systems with dependent identically distributed components. Eur J Oper Res 240:425–430
Gurler S (2012) On residual lifetimes in sequential \((\text{ n }-\text{ k }+1)\)-out-of-n systems. Stat Pap 53:23–31
Gurler S, Bairamov I (2009) Parallel and \(k\)-out-of-\(n\): G systems with nonidentical components and their mean residual life functions. Appl Math Model 33:1116–1125
Kotz S, Balakrishnan N, Johnson NL (2000) Continuous multivariate distributions. Models and Applications, 2nd edn, vol 1. Wiley series in probability and statistics: applied probability and statistics. Wiley-Interscience, New York
Li X, Lu J (2003) Stochastic comparisons on residual life and inactivity time of series and parallel systems. Probab Eng Inf Sci 17:267–275
Li X, Pellerey F, You Y (2013) On used systems and systems with used components. In: Li H, Li X (eds) Stochastic orders in reliability and risk. In honor of Professor Moshe Shaked. Springer, New York, pp 219–233
Navarro J (2016) Stochastic comparisons of generalized mixtures and coherent systems. Test 25:150–169
Navarro J, Gomis MC (2016) Comparisons in the mean residual life order of coherent systems with identically distributed components. Appl Stoch Models Bus Ind 32:33–47
Navarro J, Hernandez PJ (2008) Mean residual life functions of finite mixtures and systems. Metrika 67:277–298
Navarro J, Rychlik T (2010) Comparisons and bounds for expected lifetimes of reliability systems. Eur J Oper Res 207:309–317
Navarro J, Spizzichino F (2010) Comparisons of series and parallel systems with components sharing the same copula. Appl Stoch Models Bus Ind 26:775–791
Navarro J, Balakrishnan N, Samaniego FJ (2008) Mixture representations of residual lifetimes of used systems. J Appl Probab 45:1097–1112
Navarro J, Samaniego FJ, Balakrishnan N (2011) Signature-based representations for the reliability of systems with heterogeneous components. J Appl Probab 48:856–867
Navarro J, del Aguila Y, Sordo MA, Suarez-Llorens A (2013) Stochastic ordering properties for systems with dependent identically distributed components. Appl Stoch Models Bus Ind 29:264–278
Navarro J, del Aguila Y, Sordo MA, Suarez-Llorens A (2014) Preservation of reliability classes under the formation of coherent systems. Appl Stoch Models Bus Ind 30:444–454
Navarro J, Pellerey F, Di Crescenzo A (2015) Orderings of coherent systems with randomized dependent components. Eur J Oper Res 240:127–139
Navarro J, del Aguila Y, Sordo MA, Suarez-Llorens A (2016) Preservation of stochastic orders under the formation of generalized distorted distributions. Applications to coherent systems. Methodol Comput Appl Probab 18:529–545
Nelsen RB (2006) An introduction to copulas, 2nd edn. Springer series in statistics. Springer, New York
Pellerey F, Petakos K (2002) On the closure of the NBUC class under the formation of parallel systems. IEEE Trans Reliab 51:452–454
Shaked M, Shanthikumar JG (2007) Stochastic orders. Springer series in statistics. Springer, New York
Tavangar M (2014) Some comparisons of residual life of coherent systems with exchangeable components. Nav Res Logist 61:549–556
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I would like to thank an anonymous reviewer for his/her helpful suggestions.
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Partially supported by Ministerio de Economía y Competitividad under grant MTM2012-34023-FEDER.
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Navarro, J. Distribution-free comparisons of residual lifetimes of coherent systems based on copula properties. Stat Papers 59, 781–800 (2018). https://doi.org/10.1007/s00362-016-0789-0
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DOI: https://doi.org/10.1007/s00362-016-0789-0