水科学中应用数理统计方法应注意

对回归方程误差的影响因素进行了分析，导出了回归方程的均方误差与其影响因素之间的关系式。分析表明，复相关系数(或相关系数)一定时，倚变量的变差系数越大，回归方程的均方误差就越大；回归分析时，应对回归方程的误差进行分析。对于样本均值估计总体均值，给出了基于误差限制的样本容量的计算式。研究表明，应考虑样本变差系数对估计精度的影响。

Problems of Application of Mathematical Statistics Method in Water Science

The influencing factors for errors in regression equation are discussed and the relations between mean square error of regression equation and its influence factors are deduced.The Analysis shows that the bigger the variation coefficient of dependent variable,the bigger the mean square error of regression equation when the multiple correlation coefficient(or correlation coefficient) is definite.The error of regression equation should be analyzed when using regression analysis method.The calculation formulas of sample size based on the error limitation are given for estimation of population mean.The research shows that influence of sample variation coefficient on estimated accuracy should be considered.