booster = 'gbtree' 
objective =  'binary = logistic' 
eval_metric =  'logloss' 
max_depth = 18 
Lambda = 2.1 
n_estimators = 50  
gamma = 0.01 
subsample = 0.92 
colsample_bytree = 0.75 
min_child_weight = 4 
eta =  0.024 
seed = 1 
ROUNDS = 2000