Re: Solve for parameters of a truncated normal distribution

*To*: mathgroup at smc.vnet.net*Subject*: [mg122914] Re: Solve for parameters of a truncated normal distribution*From*: Ray Koopman <koopman at sfu.ca>*Date*: Wed, 16 Nov 2011 04:44:36 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <j9tga2$n91$1@smc.vnet.net>

On Nov 15, 2:52 am, paul <paulvonhip... at yahoo.com> wrote: > I'm trying to solve the following problem: > X = TruncatedDistribution[{0, \[Infinity]}, > NormalDistribution[\[Mu], \[Sigma]]] > Solve[Mean[X] == 1 && Variance[X] == 1, {\[Mu], \[Sigma]}, Reals] > > I get an error message: "This system cannot be solved with the methods > available to Solve." It doesn't help if I replace Solve with NSolve. > > In case I've made a mistake in defining the problem, I should say > that I'm looking for the parameters of a normal distribution so that, > if the normal is truncated on the left at zero, the result will be a > truncated distribution whose mean and variance are both 1. It seems > to me Mathematica should be able to solve this, at least numerically. > > Many thanks for any suggestions. See "Left truncated normal distribution", https://groups.google.com/group/sci.stat.math/msg/374148b83b1b73f5