# prediction score in decision tree

In this article http://xgboost.readthedocs.io/en/latest/model.html under the caption Tree Ensemble, the diagram shows 3 prediction score under the 3 nodes, +2, +0.1, and -1. How were these numbers derived? The article gave no clue.

• I believe they are just for illustration. You compute the predictions from the regression trees in a gradient booster in the same way as any other regression tree: as the mean of y over all the training samples share the same leaf node as the given sample point. Jul 23 '17 at 22:25
• stats.stackexchange.com/questions/353406/… .. please answer here if you found it Jun 27 '18 at 14:40