Keiff and Jimmer tied at Eff = +17.00 (taken from NBA.com/Players). Notice brother Marcus Morris was 4th place behind Kyrie Irving the #1 pick in the draft.
These numbers do not predict how these rookies will play in the regular season. But it is fun to see the Suns rookie do well this pre-season.
edit: How do many NBA coaches quickly evaluate a player's game performance? They check his efficiency.
NBA.com evaluates all players based on the efficiency formula:
((Points + Rebounds + Assists + Steals + Blocks) - ((Field Goals Att. - Field Goals Made) + (Free Throws Att. - Free Throws Made) + Turnovers)).
