Determining parameters of lognormal distributions from minimal information.

The lognormal distribution has a number of properties that do not lend themselves to simple "back-of-the-envelope" calculations. Mathematical relationships are presented for the basic parameters of the large population lognormal distribution as a function of characteristics available to, or needed by, the risk analyst. A freeware computer program called LOGNORM4 has been written to take the tedium out of determining various characteristics of lognormal distributions, given 1 of 15 sets of values that uniquely specify a lognormal distribution.