From: jmb184@frontiernet.net (John Bailey) Subject: Re: Decomposing a probability density function Date: Sat, 05 Feb 2000 13:32:45 GMT Newsgroups: sci.stat.math,sci.math,comp.soft-sys.matlab Summary: Black-Scholes equation (time varying variance in financial models) On Fri, 04 Feb 2000 18:28:20 +0100, Alois Schloegl wrote: >Is there any method or algorithm for decomposing a given probability >density function into a sum (or product) of gaussian distributions? > >given: any histogram H(x) > > p(x,i) is a normal distributed probability density function of x with >mean mu(i) and variance sigma(i)^2. > > H'(x) = sum (N(i)*p(x,i)) i=1..M Your problem is close to the problem of handling time varying variance in financial models--eg Black-Scholes. A web search with the phrase stochastic volatility yields a lot of material on this subject: The document at: ftp://ftp.cirano.umontreal.ca/pub/publication/95s-49.pdf.zip may be a bit of overkill, but if your interests are financial, you may find it stimulating. John