AP Psychology: Operant Conditioning (Drill 17)

Question 1. Lin's father has been nagging her all afternoon to take out the trash. The moment she finally picks up the bag and walks toward the door, her father stops nagging. Over the next several weeks, Lin begins taking out the trash more quickly whenever her father begins to nag. Which process best describes what is happening to Lin's trash-taking behavior?

• A) Negative reinforcement, because an aversive stimulus is removed following the behavior, increasing its future frequency ✓
• B) Positive punishment, because the nagging decreases the target behavior
• C) Positive reinforcement, because Lin is rewarded with the pleasant silence that follows
• D) Negative punishment, because something is taken away following the behavior

Explanation: Lin's behavior is followed by the removal of an aversive stimulus (the nagging), and her behavior becomes more frequent as a result, the definition of negative reinforcement. (C) is a common misconception: students often label any "good outcome" as positive reinforcement, but in operant terms "positive" means something is added, and here something is removed. (D) is a tempting trap, "negative" does refer to removing something, but negative punishment requires the target behavior to decrease, and Lin's trash-taking is increasing. [Practice 1]

Question 2. A factory worker is paid based on how many widgets she assembles: for every 15 widgets completed, she receives a bonus. Her production graph shows rapid bursts of assembly followed by brief pauses right after each bonus. Which reinforcement schedule best accounts for this response pattern?

• A) Variable-ratio schedule, because reinforcement follows an unpredictable number of responses
• B) Fixed-interval schedule, because reinforcement is delivered on a set timetable of elapsed time
• C) Variable-interval schedule, because reinforcement comes at unpredictable time intervals
• D) Fixed-ratio schedule, because reinforcement follows a set number of responses and typically produces a post-reinforcement pause ✓

Explanation: A bonus delivered after exactly 15 completed units is reinforcement tied to a fixed number of responses, a fixed-ratio schedule. The brief pause after each bonus is characteristic of fixed-ratio schedules. (A) is close because both ratio schedules produce high rates, but variable-ratio schedules do not produce post-reinforcement pauses, which rules it out here. (B) is true-but-irrelevant: fixed-interval schedules exist and produce scalloped response patterns, but reinforcement here is tied to widget count, not elapsed time. [Practice 3]

Question 3. A trainer is working with a dolphin that has never performed any acrobatic behavior. Over several weeks, the trainer rewards the dolphin first for breaking the surface of the water, then only for lifting its body higher each time, then only for a partial spin, then only for a complete aerial spin. Eventually the dolphin performs full aerial spins on cue. Another trainer watching suggests the dolphin could have learned the full spin just as quickly if it had been rewarded only when the complete spin occurred naturally. Which of the following best evaluates the second trainer's suggestion?

• A) She is correct; waiting for the full behavior would work as long as the reward is large enough
• B) She is incorrect; without reinforcement of successive approximations, a complex behavior like a full aerial spin is unlikely to occur at all, so there would be nothing to reward ✓
• C) She is correct, but only if the dolphin has observed another dolphin perform the behavior first
• D) She is incorrect; the dolphin would instead acquire the full spin through classical conditioning of a reflex

Explanation: Complex behaviors that an organism does not already perform spontaneously need to be built up step by step through reinforcement of successive approximations; this is shaping, and it's necessary because waiting for the full behavior to occur on its own would mean waiting indefinitely. (C) mixes in observational learning, which is a different mechanism and not what the trainer is doing. (D) is true-but-irrelevant: classical conditioning is a real learning process, but it involves pairing stimuli to produce a reflexive response, not building a voluntary complex action through reinforcement. [Practice 1]

Question 4. A high school teacher wants to test whether token rewards increase the rate at which students turn in homework. She randomly assigns one class to receive a token for each completed assignment (redeemable for a small prize) and another class to receive no tokens. After six weeks, she compares completion rates between the two classes. Which of the following is the dependent variable?

• A) Whether students receive tokens
• B) Homework completion rate over the six-week period ✓
• C) The type of small prize offered to students
• D) Random assignment to the token or no-token class in the context described

Explanation: The dependent variable is what is measured to see if the manipulation had an effect, in this study, the homework completion rate compared between groups. (A) is the independent variable (the manipulated factor: tokens vs. no tokens). (D) is true-but-irrelevant: random assignment is a strength of the design that supports causal inference, but it is not the DV, a common confusion for students who see "random assignment" and select it because it sounds methodologically important. [Practice 2]

Question 5. A preschool teacher notices that stickers, which the children can exchange for extra playground time, work extremely well as rewards for completing cleanup tasks. Which of the following statements about the stickers is most accurate?

• A) Stickers are secondary reinforcers, because their reinforcing value depends on their association with something the children already value ✓
• B) Stickers are primary reinforcers, because they directly satisfy a biological need
• C) Stickers are conditioned stimuli operating within a classical conditioning paradigm
• D) Stickers work only because they act on dopamine pathways, unlike primary reinforcers

Explanation: The stickers don't meet any biological need; they work because children have learned to associate them with something they already want (playground time). That is what makes something a secondary, or conditioned, reinforcer. (B) is wrong because primary reinforcers like food or water satisfy biological needs directly, which stickers do not. (D) is true-but-irrelevant: dopamine is involved in the reward system that makes reinforcers work, but it is involved in both primary and secondary reinforcement, so the contrast the answer draws is inaccurate. [Practice 1]