topic Outlier Deletion in Discussions

Outlier Deletion

viskovicz00012 — Sun, 16 Feb 2020 14:07:56 GMT

Is there a way to script the deletion of extreme outliers per column? My objective is once i run the script, it concatenates data tables, delete extreme outliers per column and display graphs but im having some sort of problem with the outlier part.

Re: Outlier Deletion

tom_abramov — Mon, 17 Feb 2020 16:13:58 GMT

I use Jackknife Distances for outliers.

For extreme outliers I use upper limit = 6.

In the following example I use upper limit = 2.

Names Default To Here( 1 );
dt = Open( "$SAMPLE_DATA/Big Class.jmp" );
JackknifeObj = dt << Multivariate( Y( 4 ), Jackknife Distances( 1, Save Jackknife Distances( 1 ) ) );
JackknifeObj << Close Window();
dt << Select Where( :Jackknife Distances > 2 );
dt << Hide and Exclude << Clear Select << Delete Column( Jackknife Distances );

Re: Outlier Deletion

txnelson — Sun, 16 Feb 2020 22:46:02 GMT

@tom_abramov approach is a good method for identifying outliers. Are you looking for what method to use to identify outliers or do you already have a method of determining the outliers that you want to use?