The Village Well

In the heart of Bihar, a village gathers around a shared well. Each family must choose -- contribute to its upkeep, or let others bear the cost. The well sustains all, but only if all sustain the well.

Economics Simulation

The Public Good Game

Can a group of strangers cooperate for the common good, or will self-interest prevail? Experience the free-rider problem firsthand.

How It Works

Each round, you and 4 AI players each receive 100 tokens. Decide how many to contribute to a shared pot. The pot is multiplied by 1.6x then split equally among all 5 players. Keep what you don't contribute.

Rounds

Players

1.6x

Multiplier

100

Tokens / Round

Round

1 / 10

Your Earnings

Avg Contribution

Your Contribution ? Public Good: A resource everyone benefits from, regardless of who pays. The multiplier (1.6x) means the group earns more when everyone contributes, but any individual can profit by free-riding on others' contributions.

How many of your 100 tokens will you put in the public pot? ? The Multiplier: All contributions are pooled and multiplied by 1.6, then split 5 ways. If everyone puts in 100, each gets back 160. But if only you contribute 100 and others contribute 0, you get back only 32 while keeping nothing.

Keep all (0) Give all (100)

Contribute

Keep

Game Over

10 rounds of the Public Good Game are complete. Here are the results.

The Free-Rider Problem

Arjun consistently contributed less than the group average while still receiving an equal share of the multiplied pot. This is the free-rider problem -- individuals benefit from public goods without paying their fair share.

Nash Equilibrium

The Nash equilibrium in this game is for everyone to contribute 0 tokens -- no individual can gain by contributing more if others don't. Yet this leads to the worst collective outcome.

Pareto Optimum

The Pareto optimal outcome is for everyone to contribute 100 tokens. Each player would earn 160 tokens per round (1,600 total) instead of just 100. Cooperation beats defection -- if everyone does it.

Real-World Parallels

Taxes, vaccination, climate action, open-source software -- all public goods face this exact tension between individual self-interest and collective welfare.