Paul Tench：
"... a fall represented speaker dominance, i.e. the speaker knows and tells, or the speaker assumes authority in influencing the addressee’s action, or the speaker expresses primarily their own feelings in social interaction;
and a rise represented speaker deference, i.e. the speaker does not know and asks, thereby deferring to the presumed superior knowledge of the addressee, or the speaker leaves the final decision for action to the addressee, or the speaker considers the addressee's feelings in social interaction. ... "
