Aside from giving either reinforcement or punishment, the schedule of reinforcements should also be taken into consideration to modify behaviors. Reinforcement schedules can be continuous or intermittent. In continuous reinforcement, the reinforcer is given every time a particular response occurs. For example, a cookie is given whenever a child greets the visitor. Intermittent or partial reinforcement is given only on some occasions to enhance favorable behavior. For example, a cookie is given when a child greets the visitor during the day and not during the night.
Four Types of Intermittent Reinforcement Schedules
The four types of intermittent or partial reinforcement schedules are:
1. Fixed-ratio schedule – reinforcement is given after a set number of responses. For example, a real estate agent earns an additional 1% commission after every two houses he sells.
2. Variable-ratio schedule – reinforcement is given only after an unpredictable average number of responses. This kind of reinforcement is popular in gambling or lottery where the chances of winning cannot be determined. This schedule creates a high steady rate of responding and a brief pause after receiving the reinforcer but immediately resumes the response. For example, a call center agent keeps on calling households because he/she never knows when he/she gets the bonus the management are given randomly.
3. Fixed-interval schedule – reinforcement in given only after a set amount of time. This kind of reinforcement schedule causes a high amount of responding near the end of the interval and decreases gradually after receiving the enforcer. For example, employees tend to work with vigor when payroll day is near but they gradually lose enthusiasm the day after.
4. Variable-interval schedule – reinforcement happens after a particular average amount of time. This schedule causes a slow but steady rate of response. For example, not knowing when and how many times the boss might appear during the week for inspection, the production workers are always on their toes.
My thought:
At first, it is really very hard to distinguish between the 4 intermittent reinforcement schedules because the term only differs in the middle term - ratio versus interval. How to differentiate between fixed-ratio and fixed-interval and between variable-ratio and variable-interval schedule? Since you already knew what fixed and variable is, the focus is on the middle term - ratio and interval. Just remember, for ratio - it refers to the number of responses while interval pertains to the timing of the reinforcers. I hope this clarification helps on your understanding of the concepts.
Images from
http://www.successfulthings.com/products/realestate/RealEstate/Marketingletters/agent1.gif
http://images.flatworldknowledge.com/stangor/stangor-fig07_009.jpg
http://www.happypayday.com/payday/paydaybig.jpg
http://www.trikeen.net/bigpic/workers_at_dvd_case_production.jpg
References
Cherry, K. Variable-Interval Schedule. In About.com. Retrieved from http://psychology.about.com/od/vindex/g/def_variableint.htm
Cherry, K. What Is a Fixed-Interval Schedule?. In About.com. Retrieved from http://psychology.about.com/od/findex/g/def_fixedinterv.htm
Cherry, K. What Is a Fixed-Ratio Schedule?. In About.com. Retrieved from http://psychology.about.com/od/findex/g/def_fixedratio.htm
SparkNotes Editors. (2005). SparkNote on Learning and Conditioning. Retrieved June 12, 2013, from http://www.sparknotes.com/psychology/psych101/learning/section2.rhtml
