PS101, Lec 10: 02/21/2013
Fixed ratio: # of work produce = constant # of rewards.
Fixed interval: Very reliable, checking mail everyday at the same time.
Favorite ex. Of variable ratio: Gambling, you can buy tickets all your life and never win or you can buy
them once and win.
Progressive ratio: a way to determine
How much is the subject willing to work to get something. Each time they get reinforced for behavior. Ex. If
starbucks had a program where you use your ID to get coffee and the first drink would be a penny, the more
you buy, the more progressively expensive it gets till you get a regular price. The breaking point is
when they charge you too much money for coffee.
Second Order: related to 2 order conditioning we talked about last time.
Choice: usually there’s 2 levers, if they press the left enough times, you get cocaine. If you press right
enough time, you get a milk shake. If the milk shake is too little and there’s more cocaine they press the left.
You can increase the value of one reward to get them to press the desired lever.
When people get addicted to drugs they learn to make it a habit.
Relapse is the #1 problem with drug addiction. It’s not hard to quit, it’s hard to not go back.
Forms of learning:
Observational Learning: by example
Also called vicarious conditioning: imitation.
Bobo doll expirement. Kids watch different movies with bobo dolls. When they were showed a
person kicking the doll, they kick the doll. If they watched a person playing and interacting with it, they do