采用多阶段整群分层抽样方法。

Multistage stratified cluster sampling method was used for the sampling.

youdao

方法进行问卷调查；采用多阶段整群分层抽样方法。

Methods Questionnaire and multistage stratified cluster sampling method were used for the survey.

youdao

方法进行问卷调查；采用多阶段整群分层抽样方法。

Methods Questionnaire and multistage stratified cluster sampling method were used for the survey.

youdao