喺統計學入面，大數定律係指重複做同一個實驗，樣本數量越多，咁啲結果嘅算術平均值就有越大嘅機會接近個期望值。
In statistics, the law of large numbers refers to the fact that the same experiment is repeated and the larger the sample size, the greater the chance that the arithmetic mean of some results will be close to the expected value.