Imputation of missing values

[deltaskipper]

Problem statement: I have a data set flying which consist of  variables:

[1]origin [2]destination [3]carrier [4]delay

Now I want to replace the missing value in variable delay with average delay on the specific route(source-destination) and carrier.

If i use proc stdize for imputation it replace  the missing value with the average of variable delay which I dont want to do.

Any suggestion/help will appreciate.

My code :

proc stdize data=flight missing=mean reponly  out=missing_flight;
var air_time;/* delay*/
by  origin dest carrier notsorted ;
run;

It shows some warning :

WARNING: At least one of the scale and location estimators of variable air_time can not be computed. Variable air_time will not be

standardized.

 After that I check my missing values in the output dataset  missing_flight . It is still missing and imputation is not done.

what am I doing wrong here?

[Reeza · Accepted solution]

Add a BY statement to PROC STDIZE to group by source/destination. 

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@deltaskipper wrote:

Problem statement: I have a data set flying which consist of  variables:

[1]origin [2]destination [3]carrier [4]delay

Now I want to replace the missing value in variable delay with average delay on the specific route(source-destination) and carrier.

If i use proc stdize for imputation it replace  the missing value with the average of variable delay which I dont want to do.

Any suggestion/help will appreciate.

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[Reeza]

FYI if you respond by editing your original post no one knows what was changed, what is new and it won’t come across as a new post. You’re better off replying than editing your original question.

[deltaskipper]

Yeah from next time. I keep this thing in mind.
And yes thanks for advice.

[PGStats]

Maybe you misinterpreted what NOTSORTED means in the BY statement. NOTSORTED means that the data is grouped by the origin, dest, and carrier variables, but that they are not in ascending or descending order. Try sorting your data prior to calling STDIZE without the NOTSORTED keyword.

[deltaskipper]

Thats work.
Thank you for that