There are different views on those. Keirsey actually said SJ=Melancholic and NF=Choleric. (And he rejected the functions). I believe NF=Phlegmatic (or supine), and NT is Choleric. Another level of temperament (even though it's not usually called that) is Interaction Style as well. Both dom. Te's, for instance, are In Charge or Choleric: EST(J); EN(T)J.