continue with (IV) and (DV)

[michaeladamkatz]

After introducing "predictor" and "outcome" as preferred terms to IV and DV, for a while the book continues to say "predictor (IV)" and "outcome (DV)" for several sections. But by section 2.7 it seems to fall back to just "predictor" and "outcome". I understand the reasons for preferring those words, but still I have to stop and think each time I see them, and I'd prefer if the (IV) and (DV) continued to be next to those words throughout the book.