“…, X n . For more details on this topic, one may refer to Boland (2001), Samaniego (2007), Triantafyllou and Koutras (2008), Samaniego et al (2009), Navarro et al (2010, Mahmoudi and Asadi (2011), etc. The mixture representation of the reliability function of the coherent system has been found to be useful to obtain stochastic comparison results and many researchers have discussed this topic; see, for example, Navarro et al (2005), Li and Zhang (2008), Navarro et al (2008), Zhang (2010b), Eryılmaz (2011a,b) and Burkschat and Navarro (2013).…”