Listeners' boredom: How long can the voice information of a smart speaker be?

Background If the length of voice information provided by a smart speaker is too long, the user may feel bored. On the contrary, even if the length of voice information is too short, the user may feel that the amount of information is insufficient. Therefore, in the case of long voice information provided by a smart speaker such as encyclopedia information, a guideline is needed for the length such that the user feels that there is a sufficient information amount without being bored. Methods An experiment was conducted to hit a bell when the participant felt enough information or boredom while listening to long sentences with a different number of words per sentence and speech speeds. We also analyzed the length of voice information at the time of hitting the bell. Results As a result of the experiment, the content of information, average length of sentences, and speed of speech did not affect the time when the user hit the bell. The length of voice information was about 300 Korean characters for participants that felt sufficient information without being bored. The length of voice information was about 450 Korean characters for participants that felt bored. Conclusions The results of this study can be used as a guideline for determining the length of information such as encyclopedias, news and weather provided by smart speakers.