Creates a new variable in the form of a dummy variable for a variable that contains a missing value, which identifies the missing information for that variable

In SPL, A.mi()and P.mi() can automatically generate a dummy variable to flag the missing information

For example, mark the missing values in titanic.csv:

A2 An MI_Age variable is automatically generated to flag if Age is missing

Note: Before the MI variable is generated, the mi() function will calculate the missing rate of the variable. When the missing rate is less than 5% or greater than 95%, the MI variable is not generated, but null is returned

A4 Flag the missing information for all fields, you can see that only the 6th and 11th fields generate the MI indicator variable, the others return null.