Task: Question Answering
Input (English): We end up with two salient roles called Anchors and Punctual speakers:

the Anchor speakers (A) are above the threshold of 1% for both criteria, meaning they are intervening often and for a long time thus holding an important place in interaction;

the Punctual speakers (PS) on the contrary are below the threshold of 1% for both the total number of turns and the total speech time. 
 Question: How many categories do authors define for speaker role?
Output (English):  two salient roles called Anchors and Punctual speakers