Psychology: The Basics of Trial and Error Learning (with examples)
Learning by trial and error is when you are attempting to reach a desirable outcome, and you try different methods to achieve that goal until you are successful in finding one that works. It explains learning that cannot be adequately explained by classical conditioning or behaviour not dependent on learning.
Example 1: Tara the Toddler
Tara is in the supermarket with her mother, when she sees some lollies. Tara then decides she wants to get one. That is the desirable outcome... to get the lolly.
Tara asked her mother for the lolly politely, but her mother said no and kept on walking. A possible way to get the lolly was tried, and it did not work.
Tara then grabs the lolly off the shelf and throws it in the shopping trolley. Tara's mother puts the lolly back on the shelf, and smacks Tara's hand lightly. "No, Tara! Don't do that! You can't have a lolly!" Tara just tried another possible way of getting the lolly. Once again, it didn't work. In trial and error learning, it can sometimes take a while for a way to reach the desired outcome to be revealed.
Tara then lies down on the floor of the supermarket and starts screaming. People start to stare and Tara's mother begins to get embarrassed. She tells Tara that she'll buy the lolly if she gets off the floor right this second. Tara does, and she gets the lolly.
Through trial and error learning, Tara learned that throwing a tantrum resulted in the lolly. She is more likely to repeat the behaviour of throwing a tantrum in the future if she wants another lolly.
Example 2: Wally the Accountant
Wally is an accountant who has no friends, but really wants to be popular.
He buys a joke book, because he decides the best way to make friends is to make somebody laugh. This is the desired outcome. He wants to tell a joke and for people to laugh at it. He reads the first joke in it:
Why didn't the skeleton jump off the cliff?
He didn't have the guts to!
Wally smiles. He thinks it's a funny joke. So he then walks up to someone and tells them the joke. They don't laugh. In fact, they run away from him. This decreases the probability of Wally repeating that joke, because it had a negative outcome. He wanted somebody to laugh, not run away.
He reads the second joke in his book: This is the trial and error part. He tried joke one, and it didn't work, so he's moving on to joke 2.
What kind of murderer has moral fibre?
A cereal killer.
Wally doesn't understand the joke, but tells it to somebody anyway. They start laughing, and tell him he's very funny.
Wally is more likely to repeat that atrocious joke, because telling it had the desired outcome- somebody laughing at it.
So that, my friends, is the bare bones of trial and error learning.
Get it? Got it? Good.
The Law of Effect
The law of effect suggests that behaviour that has satisfying consequences is more likely to occur in the future. Likewise, behaviour accompanied by annoying or painful consequences is less likely to be done again in the future. Thorndike developed this law after observing cats in his experiments.
The Experiments of Edward Thorndike: Cats and Puzzle Boxes
Edward Thorndike, an American psychologist, conducted trial and error emperiments on cats in the early 1900s. In these experiments, he would place a hungry cat in a special box he named the "Puzzle Box". He would put some pieces of fish outside of the puzle box, so that the cat could smell (and sometimes see) the fish, but could not reach it.
The puzzle box had a latch that would release the door to the box. Once the cat operated the lever, it would be able to escape the box and eat the fish.
The cats would try numerous ways to get out of the cage, such as squeezing through the bars, or clawing their way out. Then they would accidentally push the lever, and the cage would open. Over many different trials of the same experiment, the cat would become faster. After around seven trials, the cat would go directly to the lever and push it immediately. It remembered how to open the box.
The fact that the cat eventually would head straight for the lever demonstrates what Thorndike termed "trial and error learning". The cat had learned through making mistakes.