instrumental variable method

例句：

1. 1. The instrumentalvariable method is a statistical technique that helps researchers to control for confounding variables in their analysis.
   工具变量法是一种统计技术，帮助研究人员在分析中控制混杂变量。
2. 2. In the instrumental variable method, researchers use instruments (such as surveys orexperiments) to measure the impact of an independent variable on a dependent variable.
   在工具变量法中，研究人员使用调查或实验等工具来测量独立变量对依赖变量的影响。
3. 3. This study used an instrumental variable method to investigate the relationship between education and income inequality.
   这项研究使用工具变量法来探究教育与收入不平等之间的关系。