Model implementation for "RankFormer: Listwise Learning-to-Rank Using Listwide Labels", published at KDD 2023.

The required pip packages are listed in requirements.txt.

The code for the RankFormer method is found in model.py. Please note it imports loss functions from a separate file, i.e. loss.py. However, both files can readily be merged if necessary.

The paper's experiments simulate noisy, implicit target labels for popular Learning-to-Rank datasets (which only contain explicit labels). An implementation of this simulation is given in label_simulation.py, but the paper is best consulted to understand the various assumptions that motivate it.

main.py provides an example of this code in a simple experiment pipeline. It expects to run on the MSLR-WEB30K dataset, which can be downloaded here: https://www.microsoft.com/en-us/research/project/mslr/.

Please note that the paper's original code used a simple loss-balancing strategy to put the listwise and listwide losses on the same scale. The only impact of this difference is that the α values in the paper are on a lower scale than the list_pred_strength hyperparameter in this implementation. To obtain the same results as reported in the paper, one would therefore have to choose higher list_pred_strength values (e.g. list_pred_strength = 1 for α = 0.25). We anyway suggest that list_pred_strength is carefully tuned per dataset.

If you found this method useful in your work, please cite the paper:

@inproceedings{buyl2023rankformer,
    title={RankFormer: Listwise Learning-to-Rank Using Listwide Labels},
    author={Buyl, Maarten and Missault, Paul and Sondag, Pierre-Antoine},
    publisher={Association for Computing Machinery},
    booktitle={Proceedings of the 29th ACM SIGKDD Conference on Knowledge Discovery and Data Mining},
    series={KDD '23},
    pages={3762–3773},
    year={2023},
    doi={10.1145/3580305.3599892}
}