We have found a mistake in the proofs of Navarro (2008, Theorem 2.3(b) and 2.3(c)) due to misapplication of properties of hazard rate and likelihood ratio orders. In this paper we show with an example that the stated results do not hold. This example is interesting since it proves some unexpected properties for these orderings under the formation of coherent systems. The result stated in Navarro (2008, Theorem 2.3(a)) for the usual stochastic order is correct.
"Erratum to: Mixture representations of residual lifetimes of used systems." J. Appl. Probab. 52 (4) 1183 - 1186, December 2015. https://doi.org/10.1239/jap/1450802761