An easy-to-use equation is presented for calculating the variance of a design flood estimated using a generalised logistic distribution with model parameters estimated using single-site analysis, as described in the UK Flood Estimation Handbook. The equation is applicable for return periods in the range 2–1000 years and for annual maximum flood series with L-skewness of −0.45 to 0.45, which is considered representative of most UK flood data and practical uses.

中文翻译：

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使用广义逻辑分布估计单点设计洪水方差

提供了一个易于使用的方程，用于计算使用广义逻辑分布估计的设计洪水的方差，模型参数使用单点分析估计，如英国洪水估计手册中所述。该方程适用于 2-1000 年范围内的重现期以及L偏度为 −0.45 至 0.45 的年度最大洪水系列，这被认为代表了大多数英国洪水数据和实际用途。