Anderson, a 6-8 forward, chose DePaul over Cincinnati, Connecticut, Hawaii and Temple. Anderson is the 47th-ranked forward by ESPN Recruiting.
Robertson, a 6-9 center, also considered Southern Miss and Arkansas State. He is ranked 35th at his position.
The Blue Demons now have five commitments from the high school class of 2011.
Scott Powers covers high school and college sports for ESPNChicago.com and can be reached at email@example.com.