bpops <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  siteID <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  weight <span class="op">=</span> <span class="st">"weight"</span>,</span>
<span>  xcoord <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  ycoord <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  stratumID <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  clusterID <span class="op">=</span> <s