Creates a subset of a pedigree by retaining the ancestors of a specified subset
of individuals
Usage
prunePed(pedigree, keep, make.base=FALSE)
Arguments
pedigree
pedigree with id in column 1 dam in column 2 and sire in
column 3
keep
individuals in pedigree for which the ancestors should be
retained
make.base
logical: should ancestors that do not provide additional information be discarded?
Value
subsetted pedigree
Note
If the individuals in keep are the only phenotyped individuals for some analysis then some non-phenotyped individuals can often be discarded if they are not responsible for pedigree links between phenotyped individuals. In the simplest case (make.base=FALSE) all ancestors of phenotyped individuals will be retained, although further pruning may be possible using make.base=TRUE. In this case all pedigree links that do not connect phenotyped individuals are discarded resulting in some individuals becoming part of the base population. In terms of variance component and fixed effect estimation pruning the pedigree should have no impact on the target posterior distribution, although convergence and mixing may be better because there is less missing data.