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系统抽样在目前森林资源清查中,是一种普遍采用的抽样方法。此法较其它抽样方法有下列优点:抽取样本容易,只需一个随机数字;样本单元分布均匀;样点定位较方便。除总体单元因含有一种周期型的变差,并且当系统抽样的间距恰好与其相吻合时,抽样结果可能得到一个偏倚得很厉害的样本以外,一般说来,系统抽样往往能得到较简单随机抽样更准确的结果。本刊74年第1期上,《系统抽样与简单随机抽样精度比较试验》一文说明了这个问题
Systematic sampling is a commonly used sampling method in the current inventory of forest resources. Compared with other sampling methods, this method has the following advantages: easy to extract samples, only a random number; sample units are evenly distributed; sample positioning more convenient. In addition to the fact that the total unit contains a periodic pattern of variability and the sampling result may yield a highly biased sample when the systematic sampling interval exactly matches it, the systematic sampling will generally yield a simpler random Sampling more accurate results. This issue of 74, No. 1, the “systematic sampling and simple random sampling accuracy test” article illustrates the problem