昆虫学百分率差异显著性统计分析的简易计算方法

昆虫学定量分析资料常有2类不同性质的百分率,即组成的百分率和独立的百分率。在进行差异显著性检验时,如果样本数n较大,则组成百分率可用标准正态变量μ检验。作者给出一个简便的计算公式:μ=n0.5|P1-P2|,其中ni,nj分别为第i,j组的频次数。如果只有2组,则μ=n0.5|P1-P2|,其中P1,P2分别为第1,2组的频次数。对独立的百分率进行F检验时,如果多数数据在30%～70%之外,则应通过反正弦变换使百分率变换为角度。这种变换的实际效果往往使差异显著性提高。

A method of statistical tests of differences between percentages in entomological reseaches

There are two different kinds of percentages in entomological research which are proportions and independent percentages. For statistical test of a difference between two constituent ratios, if the number of samples is large enough, one can use the standard normal distribution variable μ test. The authors gave a simple formula: μ=|n -i-n -j|/(n -i+n -j) 0.5,where ni, nj denote frequencies of groups i and j, respectively. If groups are only two, then the formula becomes even simpler: μ=n 0.5 |P -1-P -2|, where P1 and P2 are ratios of the two groups, respectively. For F test of a difference between independent percentages, if most data are smaller than 30% or greater than 70%, a percentage, P should be transferred to an angle, α:α=sin -1(P). In fact, this transfer results generally in a more significantly difference.