Using Tenth and Ninetieth Percentiles and the Mode to Characterize Lognormal Distributions

The lognormal distribution is useful for approximating the distributions of such input variables as costs, sales, market share, etc. required in Monte Carlo simulations of business decisions.An easy way to represent such distributions is by the tenth and ninetieth percentiles and the mode.Such representation, however, does not permit direct calculation of the usual characterizing parameters (., ., and .).An empirically-determined rational function is given by which the median can be approximated from the mode, which then permits direct calculation of ., ., and ..