A Tandem Schedule of Reinforcement involves two or more basic reinforcement schedules that occur in a specific, predetermined sequence, similar to a chained schedule. However, unlike chained schedules, a tandem schedule does not use discriminative stimuli (SDs) to signal the transition between different schedules. The individual progresses through the sequence without any cues indicating which schedule is currently active.
Example
A teacher sets up a tandem schedule for a student during a math lesson. First, the student must complete 10 math problems (fixed ratio schedule), followed by staying on-task for 5 minutes (fixed interval schedule) to receive reinforcement. In this tandem schedule, there are no cues or signals to indicate the transition between completing the problems and staying on-task for the set time period. The student moves through the sequence of tasks without knowing when one schedule ends and the next begins.