In dog training, the timing and frequency of reinforcement significantly impact the learning process and the strength of the behavior being taught. Schedules of reinforcement describe how often and under what conditions a behavior is reinforced. Understanding these schedules—both thin and dense—can help trainers effectively shape and maintain desired behaviors.

Types of Reinforcement Schedules

1. Continuous Reinforcement (CRF):

• Definition: Involves providing reinforcement every time the dog performs the desired behavior.
• Application: Ideal for teaching new behaviors as it ensures that the dog makes a strong association between the behavior and the reward.
• Example: Giving a treat every time the dog sits on command.

2. Intermittent Reinforcement (Partial Reinforcement):

• Definition: Involves reinforcing the desired behavior only some of the time. This method makes the behavior more resistant to extinction.
• Types of Intermittent Reinforcement:
• Fixed Ratio (FR): Reinforcement is given after a set number of responses.
• Example: A treat is given after the dog sits five times (FR-5).
• Variable Ratio (VR): Reinforcement is provided after a varying number of responses, creating a high and steady response rate.
• Example: The dog receives a treat after an average of five sits, but the exact number varies (VR-5).
• Fixed Interval (FI): The first response is rewarded after a specified amount of time has passed.
• Example: The dog gets a treat for sitting if five minutes have elapsed since the last reward (FI-5).
• Variable Interval (VI): The first response is rewarded after varying time intervals, promoting consistent performance.
• Example: The dog gets a treat for sitting at intervals averaging five minutes, but the exact time varies (VI-5).

Thin vs. Dense Schedules of Reinforcement

1. Dense Schedules:

• Definition: These involve frequent reinforcement, where the ratio or time interval for rewards is low.
• Purpose: Dense schedules are particularly useful during the initial stages of training to rapidly establish and strengthen new behaviors.
• Example: A treat is given every time (continuous reinforcement) or after every two correct responses (FR-2).

2. Thin Schedules:

• Definition: These involve infrequent reinforcement, where the ratio or time interval for rewards is high.
• Purpose: Thin schedules are employed as the dog becomes more skilled in the behavior, promoting long-term behavior maintenance and making the behavior more resistant to extinction.
• Example: A treat is given after varying numbers of responses that average ten (VR-10) or at irregular intervals averaging seven minutes (VI-7).

Integrating Reinforcement Schedules in Dog Training

1. Starting with Continuous Reinforcement:

• Initial Stage: When introducing new behaviors, use continuous reinforcement (CRF) or dense ratio/interval schedules (FR-1, FI-1).
• Example: When teaching a dog to "lie down," give a treat every time the dog successfully lies down.

2. Transitioning to Dense Schedules of Intermittent Reinforcement:

• Intermediate Stage: Once the behavior is reliably performed, gradually transition to intermittent reinforcement to strengthen and stabilize the behavior.
• Example: Move from giving a treat every time the dog lies down (CRF) to giving a treat approximately 2 out of every 3 repetitions (VR-1.5)

3. Maintaining Behavior with Thin Schedules:

• Advanced Stage: Gradually implement thin schedules of reinforcement to maintain the behavior over the long term and increase resilience against extinction.
• Example: Provide a treat for "lie down" behaviors at varying intervals and after varying numbers of repetitions, ensuring the behavior persists even without frequent rewards (VR-10, VI-7).

Conclusion

The effective use of reinforcement schedules—both dense and thin—is crucial in dog training for developing, strengthening, and maintaining desired behaviors. By starting with dense schedules to establish new behaviors and gradually transitioning to thin schedules to promote long-term resilience, trainers can create a robust and reliable training regimen. Understanding and applying these principles help in crafting a structured and humane approach to dog training, fostering well-adjusted and obedient canine companions.