本文对中心抽样估计总体平均数的必要条件进行了论证,并对中心抽样在森林二类调查中的实用价值作了评述,认为过去对中心抽样的效率作了过高的错误评价是由于对这种方法的实质不理解而采用了错误的理论误差计算式(△=0.5s)引起的误解,中心抽样的正确理论误差计算式应该是△=ts/n~(1/2) In this paper, the necessary conditions for estimating the population averages of central sampling are demonstrated, and the practical value of central sampling in the second forest survey is reviewed. It is considered that the erroneous evaluation of the efficiency of central sampling in the past is due to the fact that The essence of the method does not understand the error theory used to calculate the formula (△ = 0.5s) caused by misunderstanding, the center of the correct theoretical error sampling formula should be △ = ts / n ~ (1/2)