Calculation of the bare and distributed counts of genes at each GO term. The nodes in the figure are GO terms, the arrows are directed from parent to child nodes. The bare count (BC) at each node is the number of genes that are placed there by the annotations of the gene lists. The distributed counts (DC) are the counts transmitted up from the children of the node. Each node contributes its total count = bare count + distributed count, equally up to each of its parents. Thus half of the total number of genes in Node 3 are contributed to the distributed counts of Node 0 and Node 4.