train.conf

# task type, support train and predict
task = train

# boosting type, support gbdt for now, alias: boosting, boost
boosting_type = gbdt

# application type, support following application
# regression , regression task
# binary , binary classification task
# lambdarank , LambdaRank task
# alias: application, app
objective = lambdarank

# eval metrics, support multi metric, delimited by ',' , support following metrics
# l1 
# l2 , default metric for regression
# ndcg , default metric for lambdarank
# auc 
# binary_logloss , default metric for binary
# binary_error
metric = ndcg

# evaluation position for ndcg metric, alias : ndcg_at
ndcg_eval_at = 1,3,5

# frequency for metric output
metric_freq = 1

# true if need output metric for training data, alias: tranining_metric, train_metric
is_training_metric = true

# number of bins for feature bucket, 255 is a recommend setting, it can save memories, and also has good accuracy. 
max_bin = 255

# training data
# if existing weight file, should name to "rank.train.weight"
# if existing query file, should name to "rank.train.query"
# alias: train_data, train
data = rank.train

# validation data, support multi validation data, separated by ','
# if existing weight file, should name to "rank.test.weight"
# if existing query file, should name to "rank.test.query"
# alias: valid, test, test_data, 
valid_data = rank.test

# number of trees(iterations), alias: num_tree, num_iteration, num_iterations, num_round, num_rounds
num_trees = 100

# shrinkage rate , alias: shrinkage_rate
learning_rate = 0.1

# number of leaves for one tree, alias: num_leaf
num_leaves = 31

# type of tree learner, support following types:
# serial , single machine version
# feature , use feature parallel to train
# data , use data parallel to train
# voting , use voting based parallel to train
# alias: tree
tree_learner = serial

# number of threads for multi-threading. One thread will use one CPU, defalut is setted to #cpu. 
# num_threads = 8

# feature sub-sample, will random select 80% feature to train on each iteration 
# alias: sub_feature
feature_fraction = 1.0

# Support bagging (data sub-sample), will perform bagging every 5 iterations
bagging_freq = 1

# Bagging fraction, will random select 80% data on bagging
# alias: sub_row
bagging_fraction = 0.9

# minimal number data for one leaf, use this to deal with over-fit
# alias : min_data_per_leaf, min_data
min_data_in_leaf = 50

# minimal sum Hessians for one leaf, use this to deal with over-fit
min_sum_hessian_in_leaf = 5.0

# save memory and faster speed for sparse feature, alias: is_sparse
is_enable_sparse = true

# when data is bigger than memory size, set this to true. otherwise set false will have faster speed
# alias: two_round_loading, two_round
use_two_round_loading = false

# true if need to save data to binary file and application will auto load data from binary file next time
# alias: is_save_binary, save_binary
is_save_binary_file = false

# output model file
output_model = LightGBM_model.txt

# support continuous train from trained gbdt model
# input_model= trained_model.txt

# output prediction file for predict task
# output_result= prediction.txt


# number of machines in distributed training, alias: num_machine
num_machines = 1

# local listening port in distributed training, alias: local_port
local_listen_port = 12400

# machines list file for distributed training, alias: mlist
machine_list_file = mlist.txt