摘要
依据近似精度，结合医学实例，对分布的近似条件进行了分析。结论如下，二项分布近似泊松分布的条件是Ｐ＜０．１。泊松分布近似正态分布的条件是λ≥１０。二项分布近似正态分布的条件是下列之一：ａ．Ｐ＜０．１，ｎｐ≥１０，ｂ．０．１≤Ｐ＜０．２，ｎ≥６０，ｃ．０．２≤Ｐ≤０．９，ｎ≥３０。
We have analyzed the approximate conditions of distributions based upon the approximately accurate requirements. A medical problem is used as an example. The results are as follows:Bernoulli distribution approximates to poisson distribution in case of P<0.1. When λ≥10, Poisson distribution is the approximation of normal distribution. Bernoulli distribution approximates to normal distribution if one of the following conditions is satisfied, that is, a. P<0.1, np≥10, b. 0.1≤P<0.2 n≥60, c. 0.2,≤P≤0.9, n≥30.
关键词
正态分布
泊松分布
二项分布
医用数学
MeSH normal distribution
poisson distribution
bernoulli distribution
