分层随机抽样法就是将总体中所有单位,按其属性、特征,分为若干类型或组、层,然后在各类型中再用简单随机抽样的方式抽取样本单位,而不是从总体中直接抽取样本单位。分层抽样可以避免简单随机抽样过于集中于某一地区、某种特性或遗漏某种特性的缺点。
采用多阶段分层随机抽样法对2岁以下儿童进行疾病状况询问调查。
Multistage stratified random sampling was conducted an interview survey in status of illness for children under 2 years old.
采用分层随机抽样法对长武王东沟小流域农业产业结构现状进行了调查分析。
This report analyzed the agricultural industry structure of Wangdonggou watershed in Changwu county based on investigation.
方法:用分层随机抽样法确定调查点。 用尼龙袋集卵孵化法、顶管孵化法分别对人畜进行查病,用系统抽样结合环境抽样法开展螺情调查。
Methods: Using stratified sampling method to determine the survey places, The schistosomiasis in people and livestock were surveyed by the methods of nylon bag incubation and top - tube incubation.
应用推荐