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== 分层随机试验步骤 ==

== 分层随机试验步骤 ==

分层随机试验在目标总体异<font color="#ff8000"> '''质性  

分层随机试验在目标总体异<font color="#ff8000"> 质性  

  Heterogeneous''' </font>的情况下非常有用， <font color="#32cd32"> 它能有效地显示研究中的趋势或特征在不同阶层（或 地层）effectively displays how the trends or characteristics under study differ between strata.</font>之间的差异。<ref name=":3" />当进行分层随机试验时，应采取以下8个步骤：<ref name=":4">{{Cite web|url=https://www.statisticshowto.com/stratified-random-sample/|title=Stratified Random Sample: Definition, Examples|last=Stephanie|date=Dec 11, 2013|website=Statistics How To|language=en-US|access-date=2020-04-07}}</ref><ref name=":5">{{Cite web|url=https://www.questionpro.com/blog/stratified-random-sampling/|title=Stratified Random Sampling: Definition, Method and Examples|date=2018-03-13|website=QuestionPro|language=en|access-date=2020-04-07}}</ref>

  Heterogeneous</font>的情况下非常有用， <font color="#32cd32"> 它能有效地显示研究中的趋势或特征在不同阶层（或 地层）effectively displays how the trends or characteristics under study differ between strata.</font>之间的差异。<ref name=":3" />当进行分层随机试验时，应采取以下8个步骤：<ref name=":4">{{Cite web|url=https://www.statisticshowto.com/stratified-random-sample/|title=Stratified Random Sample: Definition, Examples|last=Stephanie|date=Dec 11, 2013|website=Statistics How To|language=en-US|access-date=2020-04-07}}</ref><ref name=":5">{{Cite web|url=https://www.questionpro.com/blog/stratified-random-sampling/|title=Stratified Random Sampling: Definition, Method and Examples|date=2018-03-13|website=QuestionPro|language=en|access-date=2020-04-07}}</ref>