if e salience coverage <
^ e  auto SLU success NO-
RECOG then problematic iiicce duration >       then problematic if  e  salience coverage help"     e   asr  duration if e top confidence < 
CALLING CARD  then problematic if e top confidence < 
^ e asr duration >
t hen problematic Figure A subset of rules learned by RIPPER when given the automatic features for determining problematic dialogues if e top confidence ≤ 
NO-
RECOG  then problematic if e  auto SLU success    RMISMATCH  A  e  recog numwords ≤     A  e  asr duration ≥
then problematic if e salience coverage ≤
<
e  asr duration ≤ 
if  e  salience coverage help"     e   asr  duration if  e   top confidence e  asr duration ≥    then problematic if e salience coverage < A e asr duration > 
t hen problematic Figure A subset of rules learned by RIPPER when given the TASK-INDEPT features for

determining problematic dialogues
in recall and in precision  for an overall improvement in accuracy of over using the first exchange alone

## 6.3  Examination Of The Rulesets

A subset of the rules from the system that uses automatic features for Exchanges are given in Figure       row     table       One observation from these hypotheses is the classifier s preference for the asr-duration feature over the feature for the number of words recognized recog-numwords    One would expect longer utterances to be more difficult  but the learned rulesets indicate that duration is a better measure of utterance length than the number of words  Another observation is the usefulness of the SLU confidence scores and the SLU