Operant Conditioning: Skinner's 4 Cases in One Table

1. For each case ask two questions in this order. First: does the consequence ADD something (positive) or REMOVE something (negative)? Second: after the consequence, does the behavior INCREASE (reinforcement) or DECREASE (punishment)?
2. a) The sunscreen removes the sunburn, an unpleasant stimulus, so it is negative. Applying sunscreen increases, so it is reinforcement. Negative reinforcement.
3. b) The detention adds an unpleasant stimulus, so it is positive. Lateness decreases, so it is punishment. Positive punishment.
4. c) The sticker adds a pleasant stimulus, so it is positive. Tidying increases, so it is reinforcement. Positive reinforcement.
5. d) Losing the keys removes something desirable, so it is negative. Speeding decreases, so it is punishment. Negative punishment.
6. Final check: in a) and c) the behavior increases even though one case adds and the other removes. Positive and negative never mean pleasant and unpleasant, only added and removed.

Answer: a) negative reinforcement; b) positive punishment; c) positive reinforcement; d) negative punishment

1. a) False. This is the single most common error in the topic. Reinforcement, positive or negative, always INCREASES behavior; punishment always DECREASES it. Negative reinforcement increases behavior by removing something aversive, like taking a painkiller because the headache stops.
2. b) True. Reinforcement and punishment are defined by their effect, not by the intention behind them. A telling-off that does not reduce the behavior is not a punishment, and if the student was seeking attention it may even have worked as positive reinforcement.
3. c) False. Primary reinforcers satisfy biological needs: food, water, warmth. Money is a secondary or conditioned reinforcer, and its value is learned through association with what it can buy.
4. d) False. That describes classical conditioning. In operant conditioning the response is voluntary and emitted by the subject, who acts on the environment.

Answer: a) False (reinforcement always increases behavior); b) True; c) False (it is a secondary reinforcer); d) False (that is classical conditioning)

1. In escape the behavior terminates an aversive stimulus that is ALREADY present. In a) the chime is already sounding, so this is escape.
2. In avoidance the behavior prevents the aversive stimulus from appearing at all. In b) the chime never starts, so this is avoidance.
3. In c) staying home prevents the presentation, so this is also avoidance, driven by fear.
4. All three are negative reinforcement: in every case the behavior increases and what follows is the removal, or non-appearance, of something unpleasant.
5. Case c) resists extinction for a precise reason: Liam never faces the situation, so he never discovers that the feared outcome might not happen. Avoidance confirms itself, because every time it works it appears to justify itself.
6. Check: if a behavior prevents you from collecting the evidence that would disprove it, no disconfirming evidence can ever arrive. This is why avoidance keeps phobias alive.

Answer: a) escape; b) avoidance; c) avoidance. All three are negative reinforcement. The third is the most resistant because avoidance prevents the person from testing whether the feared consequence would occur, so the association is never disconfirmed.

1. First sort the ratio/interval axis: does the reinforcer depend on the NUMBER of responses (ratio) or on the TIME elapsed (interval)? Then the fixed/variable axis: is the rule constant or does it vary around an average?
2. a) The bonus depends on the number of units and it is always 50: fixed ratio (FR 50).
3. b) It depends on the number of plays, but the number varies around 30: variable ratio (VR 30).
4. c) It depends only on time, always the same amount: fixed interval (FI one month).
5. d) Every response is reinforced: continuous reinforcement (CRF).
6. e) It depends on unpredictable waiting time: variable interval (VI).
7. For the ranking, use two rules. VARIABLE schedules resist better than fixed ones, because the subject cannot tell when reinforcement has stopped and keeps responding. RATIO schedules produce higher rates than interval schedules, because responding faster genuinely brings the next reinforcer closer.
8. Resulting order, most to least resistant: b (VR), e (VI), a (FR), c (FI), d (CRF). Continuous reinforcement extinguishes fastest, because a handful of unreinforced responses is already an obvious change.

Answer: a) fixed ratio; b) variable ratio; c) fixed interval; d) continuous; e) variable interval. Resistance to extinction, most to least: b, e, a, c, d.

1. Reinforcers for A: on FR 20 one reinforcer arrives every 20 pecks, so 1840 divided by 20 = 92 reinforcers.
2. Reinforcers for B: on VR 20 the ratio is 20 on average, so the expected number is 2100 divided by 20 = 105 reinforcers.
3. Rate for A: 1840 pecks divided by 30 minutes = 61.3 pecks per minute.
4. Rate for B: 2100 pecks divided by 30 minutes = 70 pecks per minute.
5. Percentage difference: (2100 minus 1840) divided by 1840 = 260 divided by 1840 = 0.1413, which is about 14.1 per cent more.
6. Extinction prediction: B lasts longer. On FR 20, twenty or thirty pecks with no food is a clear signal that something has changed; on VR 20, long unreinforced runs are a normal part of the schedule, so the bird has no immediate way of detecting that food has stopped.
7. Consistency check: both rates are high, as expected for ratio schedules, and B is higher partly because the variable schedule lacks the post-reinforcement pause typical of fixed ratio.

Answer: A: 92 reinforcers and 61.3 pecks per minute. B: 105 reinforcers and 70 pecks per minute. B responds about 14.1 per cent more. B resists extinction longer, because on a variable ratio the unreinforced pauses are indistinguishable from the normal pauses of the schedule.

1. The constraint is that reinforcement can only act on a behavior that has already been emitted. If I wait for the final behavior I will never see it, so I reinforce behaviors that resemble it more and more closely: this is shaping by successive approximations.
2. First approximation: reinforce every time the dog approaches the door. Once this happens often, stop reinforcing mere approach.
3. Second approximation: reinforce only contact with the area around the bell, for example sniffing it.
4. Third approximation: reinforce only touching the bell with the nose or a paw, even without any sound.
5. Fourth approximation: reinforce only when the bell actually rings. Fifth and last: reinforce only when it rings and the dog then heads for the door.
6. First technical point, timing: the reinforcer must arrive within a couple of seconds. Any delay risks reinforcing whatever behavior occurred IN THE MEANTIME, such as turning away, rather than the target one.
7. Second technical point, schedule: use continuous reinforcement during acquisition, because it raises the behavior fastest. Once it is stable, switch to a variable ratio, because continuous reinforcement extinguishes quickly as soon as the treats stop.

Answer: Approximations: approaching the door, touching the area around the bell, touching the bell, making it ring, ringing it and then going to the door. The reinforcer must arrive within a few seconds or a different behavior gets reinforced. Use continuous reinforcement during acquisition and switch to a variable ratio to make the behavior resistant to extinction.

1. Starting point: whining produces the cartoon, so it is maintained by positive reinforcement. The cartoon is the consequence that makes it more probable.
2. By no longer providing the cartoon, the parents started extinction: the behavior is emitted but the consequence that maintained it no longer follows.
3. The increase over the first two evenings is called an extinction burst. It is a typical and temporary effect: when what used to work stops working, the first reaction is to try harder and more often, often with emotional or aggressive responses.
4. The burst is the phase where extinction looks like it is failing, but it is in fact the sign that the procedure is working. Had the parents held firm, the curve would have dropped over the following evenings.
5. By giving in once, however, they did the worst possible thing: they converted continuous reinforcement into intermittent reinforcement on a variable ratio, and on top of that they reinforced the most intense version of the behavior.
6. Predictable consequence: as in the slot machine exercise, the variable ratio is the schedule most resistant to extinction. The child has now learned that insisting long enough eventually works.
7. What they should have done: maintain extinction without exceptions and pair it with reinforcement of an alternative behavior, for instance giving attention when Noah asks calmly or accepts a no.

Answer: The whining was maintained by positive reinforcement; withholding the cartoon started extinction. The rise over the first two evenings is the extinction burst, temporary and normal. By giving in at the peak, the parents moved the behavior onto a variable ratio schedule, the most extinction-resistant of all, and reinforced its most intense form.

1. First limitation of punishment: it suppresses a behavior but teaches no replacement. The student learns what not to do, not what to do, so as soon as punishment is unavailable the old repertoire is still the only one available.
2. Second limitation, which explains the substitute teacher data: suppression becomes tied to the conditions in which punishment was delivered. The teacher becomes a discriminative stimulus signalling when the behavior will be punished. Outside that condition the behavior returns, because it never actually disappeared.
3. First side effect, avoidance: skipping lessons is maintained by negative reinforcement, since it removes the student from the punishing situation. Punishment has thus created a new behavior that is worse than the original one.
4. Second side effect, conditioned emotional responses: the classroom and the subject are repeatedly paired with an aversive stimulus and, through classical conditioning, end up eliciting anxiety on their own.
5. Third side effect, the tense atmosphere: punishment tends to produce hostility and aggression towards whoever delivers it, and it also models aversive control as a way of handling problems.
6. Alternative procedure. Define the desired behavior in observable terms, for example raising a hand before speaking and working quietly within the allotted time.
7. Apply differential reinforcement of an alternative behavior: systematically reinforce the desired behavior (attention, public recognition, points in a token economy) and place talking on extinction by removing the attention that often maintains it.
8. Use continuous reinforcement at first, then move to a variable ratio to make the new behavior durable.
9. Why it should work better: it builds an alternative repertoire instead of merely blocking one, it produces neither avoidance nor negative conditioned emotions, and it does not depend on the presence of the punisher, because the alternative behavior is reinforced elsewhere too.

Answer: Punishment suppresses without teaching an alternative and ties suppression to the punisher, who becomes a discriminative stimulus: hence the behavior with substitutes. The three side effects are avoidance (absences, maintained by negative reinforcement), conditioned emotional responses towards classroom and subject, and hostility towards the teacher. The alternative is differential reinforcement of the desired behavior combined with extinction of talking, using continuous reinforcement at first and a variable ratio later.

1. Deliveries in 10 minutes: 10 minutes is 600 seconds, so 600 divided by 15 = 40 deliveries per session.
2. Mechanism: food arrives on a fixed time basis and does not depend on behavior, but the pigeon is nevertheless doing something at the instant food appears. That behavior gets reinforced by sheer temporal coincidence: this is called accidental or adventitious reinforcement.
3. Once reinforced, that movement becomes more probable, so it is more likely to be under way at the next delivery, and gets reinforced again. The loop feeds itself and the response stabilises.
4. Why it persists: from the animal's point of view the behavior always works, because food keeps arriving. No evidence can ever disconfirm the association, and the apparent relationship is irregular with respect to the response, which makes it resemble a variable ratio, the most extinction-resistant schedule.
5. Human parallel: the same pattern produces good luck rituals before a test, or the fixed sequence of gestures a player performs before a free throw. An occasional success coincides with a gesture and cements it.
6. Limitation of the interpretation: in 1971 Staddon and Simmelhag re-analysed the experiment and found that many of those movements were not random. They were species-typical behaviors linked to food anticipation, so-called interim and terminal behaviors that appear at predictable points in the interval.
7. Careful conclusion: accidental reinforcement remains a plausible explanation of many superstitions, but the pigeon case shows that species-specific biological constraints help determine which behaviors appear.

Answer: 40 deliveries in 10 minutes. The behavior arises through accidental reinforcement: whatever the animal is doing when food appears gets reinforced by coincidence and becomes more probable, triggering a self-sustaining loop. It persists because food keeps arriving anyway and nothing can disconfirm the association, which resembles a variable ratio. The limitation is the 1971 re-analysis by Staddon and Simmelhag: many of those movements are species-typical food anticipation behaviors, not random responses.