Hi everyone, I made this gradient boosted tree.

bunty

my question is what are the numbers indicating at the bottom most e.g 0.018, 0.010, -0.023, -0.019 etc. ? Also, why the values are in negative? I made this gradient boosted tree. target variable (yes/no to predict arthritis from following independent variables: uric acid, white blood cells, age, gender, and C reactive protein -CRP)
e.g 0.018, 0.010, -0.023, -0.019 etc. ?