Analysis and rejection sampling of Wright-Fisher diffusion bridges

Theor Popul Biol. 2013 Nov;89:64-74. doi: 10.1016/j.tpb.2013.08.005. Epub 2013 Aug 31.


We investigate the properties of a Wright-Fisher diffusion process starting at frequency x at time 0 and conditioned to be at frequency y at time T. Such a process is called a bridge. Bridges arise naturally in the analysis of selection acting on standing variation and in the inference of selection from allele frequency time series. We establish a number of results about the distribution of neutral Wright-Fisher bridges and develop a novel rejection-sampling scheme for bridges under selection that we use to study their behavior.

Keywords: Bridge; Diffusion; Rejection sampling; Wright–Fisher.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Genetics, Population*
  • Models, Theoretical*