Van Tharp's Marble Game

Experience the power of expectancy through this interactive simulation. Learn why having an edge is more important than being right all the time.

Interactive Learning

Van Tharp Method

Expectancy Simulation

Disclaimer: This is an educational simulation based on Van Tharp's marble game concept. Results do not reflect actual trading performance and are for learning purposes only. Real trading involves additional complexities and risks not represented in this simulation.

Read full disclaimer • Please consult with a qualified financial advisor before making trading decisions.

Marble Drawing Game

Draw marbles from a bag with 3 winning marbles (+$300) and 7 losing marbles (-$100)

Leaderboard

Top performers in the marble drawing game

Rankings

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Understanding the Marble Game

What is Expectancy?

Expectancy is the average amount you can expect to win or lose per trade over the long run.

The marble game demonstrates that even with a low win rate (30%), you can still be profitable if your average win is larger than your average loss. This is the foundation of successful trading systems.

Win Rate vs Profit

Many traders focus too much on being right, but profitability depends on expectancy.

A system with 30% wins at $300 each and 70% losses at $100 each has positive expectancy: (0.3 × $300) + (0.7 × -$100) = $90 - $70 = $20 per trade.

Key Insights

The game teaches crucial lessons about trading psychology and system design.

•Focus on expectancy, not win rate
•Losing streaks are normal and expected
•Position sizing affects overall results

Discussion: Van Tharp's Marble Game

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