The economics of the law of effect.

Collier et al. (1986) asked a simple question: do rats work like shoppers in a store? They gave rats tiny food pellets for pressing a lever. Sometimes the pellet was small. Sometimes the rat had to press many times for one pellet. The team watched how fast the rats pressed under each deal.

The study used standard lab rats. No special diets. No disabilities. Just lever pressing for food. The researchers changed two things: pellet size and number of presses needed. They counted presses per minute. That was the data.

Rats pressed faster when the pellet got smaller. They also pressed faster when the price went up. In plain words, less food per press made them work harder, not less. The law of effect still ruled, but it looked like economics.

The results matched a shopping rule: when coffee costs more or the cup shrinks, people buy more cups to get the same buzz. Rats did the same with food.

Evans et al. (1994) repeated the idea with water. Rats spread their licks across bottles the same way they spread lever presses across food. Same economic brain, different drink. This backs up the 1986 story.

Bailey et al. (1990) added risk. When food was plenty, rats picked the safe, steady pellet instead of the risky jackpot. This extends the 1986 price rule: both price and safety guide choice.

Kelly (1973) came earlier and showed that timing of rewards changes response speed. Collier et al. (1986) wrapped that old finding in a price tag. The new paper does not cancel the old one; it just explains it with dollars and cents.

You already adjust token boards and break sizes. This paper says tiny breaks or leaner token pay can boost work rate, as long as the task stays doable. Try cutting a 10-minute break to 5 minutes while keeping the same task demand. Watch if your learner speeds up. You are testing the unit-price rule in real life.