Computation of sample mean range of the generalized laplace distribution

A generalization of laplace distribution with location parameter θ,-∞ < θ < ∞,and scale parameter ϕ > 0,is defined by introducing a third parameter α > 0 as a shape parameter. one tractable class of this generalization arises when α is chosen such that 1/α is a positive integer. in this article,we derive explicit forms for the moments of order statistics,and the mean values of the range,quasi-ranges,and spacings of a random sample corresponded to any member of this class. for values of the shape parameter α equals 1 / i,i = 1,...,8,and sample sizes equal 2,3,...,15 short tables are computed for the exact mean values of the range,quasi-ranges,and spacings. means and variances of all order statistics are also tabulated.