“…Statistical methods dealing with the properties and applications of the half-normal distribution have been extensively used by many researchers in diverse areas of applications, particularly when the data are truncated from below (that is, left truncated,) or truncated from above (that is, right truncated), among them Dobzhansky and Wright (1947), Meeusen and van den Broeck (1977), Haberle (1991), Altman (1993), Buckland et al (1993) , Chou and Liu (1998), Klugman et al (1998), Bland and Altman (1999), Bland (2005), Goldar and Misra (2001), Lawless (2003), Pewsey (2002Pewsey ( , 2004, Chen and Wang (2004) and Wiper et al (2005), Babbit et al (2006), Coffey et al (2007), Barranco-Chamorro et al (2007), and Cooray and Ananda (2008), are notable. A continuous random variable X is said to have a (general) half-normal distribution, with parameters μ (location) and σ (scale), that is, X |μ, σ → H N (μ, σ ), if its pdf f X (x) and cdf F X (x) = P(X ∈ x) are, respectively, given by…”