更改

在上面的例子中，如果Z和X是二进制值，那么Z=0，X=1不出现的假设称为单调性。

在上面的例子中，如果Z和X是二进制值，那么Z=0，X=1不出现的假设称为单调性。

对该技术的改进{{clarify|reason=What technique?|date=January 2019}}包括通过调节其他变量{{clarify|reason=What other variable are we talking about?|date=January 2019}}来创建工具变量{{clarify|reason=What is an instrument?|date=January 2019}}，以阻断{{clarify|reason=What does it mean to "block a path"?|date=January 2019}}工具变量和混杂因子{{clarify|reason=What cofounder are we talking about?|date=January 2019}}之间的路径{{clarify|reason=What is the exact definition of a path?|date=January 2019}}，并组合多个变量以形成单个工具变量{{clarify|date=January 2019}}。<ref name=":1" />

对该技术的改进包括通过调节其他变量来创建工具变量{{clarify|reason=What is an instrument?|date=January 2019}}，以阻断工具变量和混杂因子之间的路径{{clarify|reason=What is the exact definition of a path?|date=January 2019}}，并组合多个变量以形成单个工具变量。<ref name=":1" />

===== 孟德尔随机化 Mendelian randomization =====

===== 孟德尔随机化 Mendelian randomization =====