How to work around the missing cases of vis?

1. How should Missing observations be handled?
2. How do you prove missing at random?

How should Missing observations be handled?

One way of handling missing values is the deletion of the rows or columns having null values. If any columns have more than half of the values as null then you can drop the entire column. In the same way, rows can also be dropped if having one or more columns values as null.

How do you prove missing at random?

Missing at Random: MAR

If there is no significant difference between our primary variable of interest and the missing and non-missing values we have evidence that our data is missing at random.