Happy is an r interface into the happy c package for fine-mapping quantitative trait loci (qtl) in heterogenous stocks (hs). an hs is an advanced intercross between (usually eight) founder inbred strains of mice. hs are suitable for fine-mapping qtl. it uses a multipoint analysis which offers significant improvements in statistical power to detect qtls over that achieved by single-marker association.

the happy package is an extension of the original c program happy; it uses the c code to compute the probability of descent from each of the founders, at each locus position, but the happy packager allows a much richer range of models to be fit to the data.

read /usr/share/doc/r-other-mott-happy/readme.debian for a more detailed explanation.