Andi's statement that "All of us are novelists" clearly cannot be true.  If it were true, Andi would be a novelist and hence a liar, and hence her statement would be false which would mean there is at least one person who is not a novelist.  We have confirmed that Andi is a liar (and hence a novelist) and that there is at least one non-fiction writer (a truth teller).  Given that all the statements assert a different number of novelists , only one can be true.   So the only statement that can be true is the one that states that there are three novelists.  This statement is made by Baye, who must be a non-fiction writer.  Everyone else must be a novelist.