Filler rules

Filler rules in grammars are when you define the optional words and phrases that a caller might say. Since you define common unimportant words in filler rules, the confidence level of the recognition is usually higher. However, the larger a grammar increases in size, the lower the confidence levels might descend without further tuning. To use filler rules in grammars, ensure that you include only those unimportant rules that a majority of IVR callers use. Defining filler rules with unimportant words that callers say infrequently or not at all impacts the efficiency and accuracy of speech recognition.