Subsampling within Group

[abak]

I need to subsample a dataset within groups. Here is an example- two columns.

Group       Data

G1             v1

G1             v2

G1             v3

G1             v4

G2             v5

G2             v6

G3             v7

G3             v8

G3             v9

G3             v10

G3             v11

I actually have a lot more data points for some groups. For the groups with more than 2 (for example), I want to only sample 60% of the values from that group in a subset.

How do I accomplish that?

[PGStats · Accepted solution]

You could use proc surveyselect and specify your sample sizes in a secondary dataset

proc sql;
create table sampleSize as
select 
    group,
    max(2, 0.6*count(*)) as _nsize_
from myData
group by group;
quit;

proc surveyselect data=myData selectall out=mySample sampsize=sampleSize;
strata group;
run;

(untested)

[abak]

Thank you! The only thing missing was round. Easily added!

round(max(2, 0.6*count(*)))