The Law of Large Numbers and Gambling
What is the Law of Large Numbers?
The Law of Large Numbers is a fundamental principle in probability theory that states: as the number of trials increases, the average of the results becomes closer to the expected value.
In simpler terms: the more times you repeat a random event, the more predictable the overall outcome becomes.
How Does This Apply to Gambling?
Every casino game has a built-in advantage for the house, called the "house edge." This means:
- Short term: You might win big or lose big - anything can happen
- Long term: The house edge ensures you will lose money
Example: In roulette, betting on red has a 48.6% chance of winning (18 red numbers out of 37 total). The house edge is 2.7%.
- Bet $100 once: You might win $100 or lose $100
- Bet $100 ten times: You might be ahead or behind
- Bet $100 a thousand times: You will almost certainly be down about $2,700 (2.7% of $100,000)
Why Do Gamblers Keep Playing?
Several psychological factors keep gamblers playing despite the mathematical reality:
- Confirmation Bias: Remembering wins more than losses
- Gambler's Fallacy: Believing "I'm due for a win" after losses
- Near Misses: Almost winning feels like progress
- Variable Rewards: Unpredictable wins are more addictive
The Mathematics Behind It
Let's say you play a game with a 5% house edge:
Expected Value Calculation:
• Each bet: -5% (house edge)
• 100 bets: -5% average
• 1,000 bets: -5% average
• 10,000 bets: -5% average
The law of large numbers guarantees that as you play more, your actual results will converge toward this -5% expectation.
Key Point: No matter how much you win in the short term, the house edge ensures you will lose money over time.
What This Means for Gamblers
- Short-term wins are possible - but they're just luck
- Long-term losses are guaranteed - this is mathematics
- More gambling = more losses - the law is inexorable
- No strategy can overcome the house edge - it's built into every game
The casinos don't need to cheat - they just need you to keep playing long enough for the law of large numbers to take effect.
The AntiGamble Perspective
Our simulators demonstrate this principle:
- You can win individual games
- You might even be ahead for a while
- But over thousands of games, you will lose money
- The graph shows the inevitable decline
Understanding the law of large numbers is the first step toward responsible gambling behavior.
Getting Help
If you or someone you know is struggling with gambling:
Remember: The law of large numbers applies to everyone. No one is immune to the mathematics of gambling.