A summary of the alignments by each program to the edges of exons. A representation of an exon is shown at top, with a representation of the three possible match outcomes below, i.e., an exact match to the exon boundary, a match that ends before the exon boundary, and a match that extends beyond the exon boundary. The percentage of all matches by each program that fall into those categories are depicted as bar graphs. Left: Percentage of matches correctly aligned to either exon boundary. Middle and right: Percentage of matches incorrectly aligned to an exon boundary, with the match ending before or extending beyond a boundary, respectively.