新疆玛纳斯灌区水面蒸发量主成分分析

Principal Component Analysis of Water Surface Evaporation in Manasi Irrigation Region

对新疆玛纳斯灌区水面蒸发气象影响因子进行了主成分分析。第一主成分代表空气冷热状况;第二主成分代表空气动力条件和日照条件;第三主成分代表相对湿度。前3个主成分累计贡献率已达97.7%,故提取3个主成分已能满足要求。经过检验,利用2个主成分建立二元一次回归方程,并与应用所有气象影响因子建立的多元线性回归方程相比较,结果显示,主成分分析方法建立的回归方程的偏回归系数均通过t检验,达到极显著水平,多元线性回归方程虽拟合效果稍优于主成分分析方法,但偏回归系数b均未通过t检验,系数显著性水平不如主成分分析法。

This paper conduct principle component analysis of meteorological factors which influencing water surface evaporation in Manasi irrigation region. The first principal component stands for hot and cold air situation; the second one stands for air dynamic condition and sunshine status; and the third one stands for relative humidity status. Accumulative contribution rate of these three principal components has reached 97.7%, so to adopt these principal components could meet the demand. After testing, the binary linear regression equation was built by two principal components, and compared with multiple linear regression equation which was built by all meteorological factors. It was found that all the partial regression coefficients past t test with the level of very significance in the regression equation built by principal component. Although the fitting effect of multiple linear regression equation was a bit better than the principal component analysis method, the partial regression coefficient b didn＇t pass t test in multiple linear regression equation, and its coefficient significance level was not as high as principal component analysis method.