If the addition of query expansion enables an aligner to correctly align slide regions which its query expansionless counterpart could not, then we should see large percentages of errors being corrected when comparing aligner A to B and C to D. By comparing aligner A to C and B to D, we have a measure of the error reduction achieved by implementing scoring method 2 instead of method 1.
tables 8 and 9 show that aligner D significantly reduced aligner B's errors and aligner C significantly reduced aligner A's errors, but aligner B did not improve much on A, nor did D on C. adding query expansion did not significantly reduce errors, but using scoring method 2 instead of 1 did.