The method achieved a significant relative reduction of Word Error Rate (WER) of 5% (this is 44% of the possible WER improvement on this data), and 62% of the possible semantic improvement (Dialogue Move Accuracy), compared to the baseline policy of selecting the topmost ASR hypothesis.
if a hypothesis is erroneous as far as its transcript is concerned   The baseline for our experiments is the behavior of the Town-Info spoken dialogue system that was used to collect the experimental data.