Ted’s Public Workbench Interactive Experiments

Game Theory
Playground

Your best move depends on someone else.
What happens next?

Make a choice. See what it sets in motion. Then change the rules and try again. Twenty small experiments explore why we cooperate, what we believe about other people, and how the rules change the result.

Start with The Trust Machine Explore all twenty

No sign-up Runs in your browser 5–10 minutes per experiment

Predict

What do you expect?

Choose

Make a move that matters.

Discover

Follow the incentives.

Change

Adjust one assumption.

Connect

Try the idea elsewhere.

A Small Dilemma

You Both Have a Choice

Cooperate, or look after yourself?

Points: you / your partner
Your choice	They cooperate	They defect
Cooperate	3 / 3Everyone gains	0 / 5You lose out
Defect	5 / 0You get more	1 / 1Both get less

Now imagine you’ll meet again tomorrow.

Play out the consequences →

The Collection

Twenty Ways to See the Game

Prototype Updated Sept. 27, 2026

Start With the Foundations

Six experiments introduce choices, cooperation, and the ways sensible decisions can collide.

Blue and orange playing pieces stand beside two matching halves of a shared bridge.

01Repeated Games

The Trust Machine

When does it pay to cooperate?

Cooperate or defect, meet your opponent again, and discover what a little forgiveness changes.

Open experiment

Two playing pieces sit on interlocking circular tracks with gates blocking the shared path.

02Nash Equilibrium

Why Are We Stuck?

Can everyone be unhappy and still stay put?

Play both sides of a two-person game. Change the payoffs and find out who has a reason to move.

Open experiment

Eight playing pieces wait on separate platforms around a shared center, with gaps between their bridges.

03Coordination

Nobody Wants to Go First

What would make your team take the first step?

Help eight teams choose a shared technology. Test expectations, pilot support, and commitments.

Open experiment

A rock, a sheet of paper, and scissors sit on a blue tray beside colored counters.

04Mixed Strategies

Can You Be Unpredictable?

Is your next move easier to guess than you think?

Face a pattern-seeking opponent, then build a random strategy and compare it with an even mix.

Open experiment

A blue gate with a brass bolt blocks one branch of a wooden path beside two playing pieces.

05Credible Commitments

Would You Actually Do It?

Will a threat survive the moment of decision?

Enter a market, make a threat, and work backward through the choices. See what a deposit changes.

Open experiment

Miniature cars crowd a central shortcut while the longer outer roads have fewer cars.

06Braess’s Paradox

The Shortcut That Made Everyone Late

Could an extra road make your commute worse?

Open a shortcut, let drivers choose their routes, and compare the result with a coordinated plan.

Open experiment

Share, Negotiate, and Learn

Eight experiments explore shared resources, bargaining, hidden information, and changing beliefs.

Four playing pieces and their small bowls surround a shared pool of counters beside a wooden pavilion.

07Public Goods

Who Pays for the Shared Benefit?

Why help pay when everyone gets the benefit?

Choose a contribution, add matching funds, and compare your points with the group’s total.

Open experiment

Small wooden fish fill a blue ceramic lake surrounded by fishing boats and baskets.

08Shared Resources

The Last Fish

How much can you take without emptying the lake?

Fish from a shared lake, change its growth and harvesting rules, and follow the stock through time.

Open experiment

Blue and orange playing pieces face a divided tray of counters across a round negotiating table.

09Bargaining

Split It or Walk Away

What makes an offer worth accepting?

Divide a shared reward, compare alternatives, and see how waiting or rejecting changes the result.

Open experiment

Three playing pieces with bowls of counters face a blue vase beside an auction gavel.

10Auctions

Congratulations, You Overpaid

What does winning actually cost you?

Compare first-price and second-price bids, then test what happens when bidders estimate a shared value.

Open experiment

An open box reveals a blue gem while a second box stays closed beside a buyer, seller, and brass seal.

11Signals and Information

Should You Believe the Signal?

Can a promise tell you what is hidden?

Try claims and costly signals, update a buyer’s expectations, and check who would want to imitate whom.

Open experiment

Four playing pieces surround a board of concentric rings with colored beads at different distances from its center.

12Expectations

I Think You Think…

How many steps ahead should you think?

Choose a number against different reasoning styles and watch the group’s target change over rounds.

Open experiment

Two playing pieces in separate lookout towers can see a shared lantern, with a sealed letter between them.

13Common Knowledge

Does Everyone Know That Everyone Knows?

Is a private message as useful as a public announcement?

Send messages and acknowledgments, compare possible delivery histories, and test what each side can know.

Open experiment

Carved blue hawks and ivory doves surround resource counters in a wooden arena as orange birds enter.

14Evolutionary Games

Survival of the Strategy

Does a successful strategy stay successful as it spreads?

Mix Hawk and Dove strategies, change conflict costs, and introduce a small invading group.

Open experiment

Design the Rules

Six experiments ask how advice, matching, voting, credit, and rewards change what people do.

A wooden box offers separate blue and orange counters beside two playing pieces and curved tracks.

15Correlated Equilibrium

Can Advice Help Everyone?

When is following shared advice your best move?

Compare independent choices with coordinated recommendations, then inspect the incentive to obey or switch.

Open experiment

Three blue playing pieces are paired with three orange pieces by cream ribbons on a wooden board.

16Stable Matching

The Matchmaker’s Dilemma

Can every pair be satisfied with the match?

Rank possible partners, step through proposals, switch who proposes, and look for pairs that want to leave.

Open experiment

Three colored wooden supports hold up one arch, with a playing piece and a bowl of rewards for each contributor.

17Coalitions and Shared Value

Who Deserves the Credit?

How much did each teammate add to the result?

Set the value of different teams, compare ways to split credit, and check whether a subgroup could do better.

Open experiment

Blue, orange, and cyan ballot boxes stand behind blank voting cards, playing pieces, and stacks of counters.

18Voting Rules

Who Actually Won?

Can the same preferences produce different winners?

Compare four voting rules, separate honest preferences from submitted ballots, and inspect ties and cycles.

Open experiment

A workshop produces many rough cubes on one side and a few smooth cubes on the other, beside a balance and reward counters.

19Incentives and Hidden Action

You Get What You Reward

Will the reward improve the work or just the score?

Choose a reward rule, inspect effort and shortcuts, and compare employee pay with the value created.

Open experiment

Four playing pieces surround one blue key, with a queue of counters, a lottery bag, and an auction gavel nearby.

20Mechanism Design

Write the Rules

Will your rules encourage people to tell the truth?

Allocate one scarce item by queue, lottery, priority, or auction, then compare truthful and exaggerated reports.

Open experiment

One More Road. A Longer Commute.

Good Intentions Meet Other People’s Choices

The Traffic Paradox puts individual choices on a shared road network. Add a shortcut, inspect the route flows, and see why the fastest route for one driver can make everyone slower.

Open the Traffic Paradox →

65 min

Before the shortcut

80 min

After drivers settle

A theoretical result for 4,000 drivers under this experiment’s default road costs. Change the assumptions and test it.

Small Models, Useful Questions

Game theory studies choices whose outcomes depend on other people’s choices. Here, you can inspect the points each player earns, replay the same random sequence, and ask which assumptions fit your own situation.

Every experiment includes step-by-step math using pre-algebra, a separate expert section with formal equations, and a scenario link. The numbers describe the model. The questions are yours to take into a team, a negotiation, or a shared project.

The learning-by-playing approach is inspired by Nicky Case’s The Evolution of Trust. These experiments use their own models and implementation.

Choose Your Own Path

Start with the first six experiments if game theory is new to you. Then follow a question that interests you: sharing a lake, negotiating a split, choosing a voting rule, or rewarding good work.

Each experiment stands on its own. The final Mechanism Design Studio brings the ideas together: choose an allocation rule, then test what it encourages people to report.

These are small teaching models. Their assumptions and tie-breaking rules are part of the explanation, so you can see what a result does and does not establish.