According to the Premack principle, what characterizes an efficient reinforcer?

• A. A higher-probability behavior
• B. A lower-probability behavior
• C. A behavior with no probability
• D. A behavior unrelated

Answer: (B)

The key idea here is that reinforcement depends on how often a behavior occurs. Under the Premack principle, a behavior that happens more often (a higher-probability, preferred activity) can serve as a reinforcer for a behavior that happens less often (a lower-probability, less-preferred activity). So, the efficient reinforcer is the higher-probability behavior, because it has the greatest motivating power to increase the occurrence of the target, less frequent behavior. For example, if a child loves video games (a high-probability activity) and tends to avoid doing chores, allowing video game time after chores completes the reinforcement for doing chores. The other options don’t fit: a lower-probability behavior isn’t a reliable reinforcer, and a behavior with no probability or an unrelated behavior wouldn’t effectively increase the target behavior.