The law of large numbers says that averaging many samples from a probability distribution produces a value close to the distribution’s expected value. With infinitely many samples, the average matches the mean; with finite samples, closeness is probable rather than guaranteed. section 5.8
This principle explains why the sample mean can estimate an unknown distribution’s true mean. No universal sample count defines “enough”: distributions with larger variance require more samples for a similarly reliable approximation. section 5.8
Casino outcomes
A casino can lose individual bets while still making money overall when its win probability is slightly higher. Across a very large number of bets, the average outcome approaches the expected casino advantage. section 5.8
