How to clean a dataset in spss

To winsorize data means to set extreme outliers equal to a specified percentile of the data.

For example, a 90% winsorization sets all observations greater than the 95th percentile equal to the value at the 95th percentile and all observations less than the 5th percentile equal to the value at the 5th percentile.

In effect, to winsorize data means to change extreme values in a dataset to less extreme values.

Example: How to Winsorize Data

Suppose we have the following dataset:

To perform a 90% winsorization on this dataset, we would first find the 5th percentile and the 95th percentile, which turn out to be:

• 5th percentile: 12.35
• 95th percentile: 92.05

We would then set any values below 12.35 equal to 12.35 and any values above 92.05 equal to 92.05:

In this case, the value 3 became changed to 12.35 and the value 98 became changed to 92.05.

Why Winsorize Data?

The mean and the s