频率具有抽象的数学意义，如果某事件的发生与否事先无法预知，只有通过大量的实测资料，用数理统计方法估算出现机率，这种机率称为经验频率。
目前，国内外已有多种多样的经验频率公式。
Now, there have been various types of empirical frequency formulas in China and other countries.
经验频率采用规范中推荐的公式计算，统计参数用矩法公式计算。
The experiential frequency is calculated with formula recommended in the standard, and statistical parameters are calculated with matrix formula method.
城市暴雨公式统计中最重要的两个环节就是经验频率的计算和频率分布模型的选择。
Calculation of empirical frequency and selection of frequency distribution model form two most important segments in the formula of urban stormy statistics.
应用推荐