In a SAS Viya gradient boosting model (gbtreetrain CAS action), a data scientist sets SUBSAMPLERATE=0.8 and COLSAMPLEBYTREE=0.7. What do these parameters together create?
Select an answer to reveal the explanation.
Short Explanation
Here's the deal — you're building a stochastic gradient boosting model when you set SUBSAMPLERATE=0.8 and COLSAMPLEBYTREE=0.7. Each tree uses 80% of randomly sampled observations and 70% of randomly sampled variables, which boosts diversity and cuts variance.
Full Explanation
The correct choice is the stochastic gradient boosting model that uses 80% of randomly sampled observations and 70% of randomly sampled variables for each tree. In SAS Viya's gbtreetrain CAS action, SUBSAMPLERATE=0.8 means each tree trains on 80% of training observations randomly sampled without replacement, and COLSAMPLEBYTREE=0.7 means 70% of variables are randomly sampled for each tree. Together these implement stochastic gradient boosting, increasing diversity and reducing variance. The option saying 80% of variables and 70% of observations transposes the parameters. The depth/leaf option confuses sampling with tree structure controls. The L1 regularization option incorrectly ties subsampling to regularization.