Figure 3.

Change in Gene Ontology category rank between the standard and GOseq methodologies. (a) Change in rank of GO categories going from the hypergeometric method to GOseq correcting for length bias plotted against the log of the average gene length of the category. (b) Change in rank of GO categories going from the hypergeometric method to GOseq correcting for total read count plotted against the log of the average number of counts of each gene in the category. A trend for the standard method to underestimate significance for GO categories containing short (or highly expressed) genes and overestimate significance for GO categories containing long (or underexpressed) genes can be clearly seen.