On 9/04/2008, at 10:30 AM, Phil Rhoades wrote: > People, > > Say a particular measure of an attribute for individuals in different > populations gives a set of overlapping normal distributions (one > distribution per population). If I then measure this attribute in > a new > individual - how do I assess the likelihood of this new individual > belonging to each of the different populations?
You have a mixture of distributions. Let the density be k f(x) = SUM lambda_i * f_i(x) i=1 where the f_i(x) are the densities for the individual components in the mixture, and the lambda_i are the mixing probabilities. The probability that an individual with observation x is from component i is lambda_i * f_i(x) ----------------- f(x) cheers, Rolf Turner ###################################################################### Attention:\ This e-mail message is privileged and confid...{{dropped:9}} ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.