XGBoost supports accomplishing ranking tasks. In ranking scenario, data are often grouped and we need the group information file to specify ranking tasks. The model used in XGBoost for ranking is the LambdaRank, this function is not yet completed. Currently, we provide pairwise rank.
The configuration setting is similar to the regression and binary classification setting,except user need to specify the objectives:
...
objective="rank:pairwise"
...
For more usage details please refer to the binary classification demo,
The dataset for ranking demo is from LETOR04 MQ2008 fold1, You can use the following command to run the example
Get the data: ./wgetdata.sh Run the example: ./runexp.sh