PTB co-founder Dana Meller delves into the differences and nuances between fixed-time (FT) and variable-time (VT) schedules, as well as fixed-interval (FI) and variable-interval (VI) schedules.

Refer to BCBA® Task List (5th ed.) Sections B-5: Define and provide examples of schedules of reinforcement; and G-14: Use reinforcement procedures to weaken behavior (e.g., DRA, FCT, DRO, DRL, NCR).