{PrefLib}: A Library for Preferences


A reference library of preference data and links assembled by Nicholas Mattei and Toby Walsh. We currently house over 3,000 datasets for use by the community. We want to provide a comprehensive resource for the multiple research communities that deal with preferences, including computational social choice, recommender systems, data mining, machine learning, and combinatorial optimization, to name just a few.

Citation Policy

We ask that you provide a reference to our repository when publishing research based on data gathered here as this will allow other researchers to find us. Additionally, some of our datasets have citation policies specific to them, please comply with these requests. Many hours have been spent to gather, organize, and publish these datasets and we want to provide credit where credit is due.

If you use data from PrefLib in a publication please let us know and we will add it to our Papers page.

Donation Policy

Please contact Nicholas Mattei via email at nsmattei{at}gmail to contribute a data set. We will host the data set and work with you on keeping it up to date. We rely on the support of the community in order to increase the usefulness and coverage of this site. Please don't hesitate to contact us!

Supported By:


PrefLib would not be possible without the support of the greater community. We would like to specifically thank the following people for their contributions to PrefLib.