Implementability (mechanism design)

Implementability is when you make a plan or a rule that is designed to help people act a certain way or achieve a certain goal, and then make sure that people will actually follow the plan or rule. It's like creating a game with rules and making sure everyone playing sticks to those rules.

Mechanism design is a fancy term for designing such plans or rules. It's like creating a blueprint or a recipe for something that you want to happen.

For example, let's say you want to encourage people to recycle more. You could design a plan that says if people bring in a bag of recyclables to a recycling center, they will get a reward like a candy or a toy. But if you just create the plan without thinking about how people will react, it might not work as well as you hoped.

Implementability is making sure that people will be motivated enough to bring in recyclables by offering them a reward, and that the reward is enough to make them want to do it again. It's also making sure that people won't try to cheat the system by bringing in non-recyclable items, and that the reward is given out fairly to everyone who follows the rules.

In summary, implementability is about making sure that a plan or rule you design actually works in practice, and mechanism design is the process of creating that plan or rule in the first place.