ACM RecSys Challenge 2019


The RecSys Challenge 2019 will be organized by trivago, TU Wien, Politecnico di Milano, and Karlsruhe Institute of Technology. trivago is a global hotel search platform focused on reshaping the way travelers search for and compare hotels, while enabling advertisers of hotels to grow their businesses by providing access to a broad audience of travelers via our websites and apps. trivago has established 55 localized platforms in over 190 countries and provides access to over two million hotels, including alternative accommodations, with prices and availability from over 400+ booking sites and hotel chains.

This year’s challenge focuses on travel metasearch. The goal of this challenge is to develop a session-based and context-aware recommender system using various input data to provide a list of accommodations that will match the needs of the user.

In the challenge, participants will be tasked with predicting which accommodations (items) have been clicked in the search result during the last part of a user session in an offline evaluation setup. To this end, trivago will release a public dataset of hotel search sessions.

A detailed description of the challenge will be made available soon (see tentative timeline).


An overview paper will be provided soon to the participants.

Participation and Data

The data for this year's challenge is provided by trivago and can be downloaded from https://recsys.trivago.cloud/. You can access the data once you create an account and agree with the terms and conditions. The information on the challenge participation can also be found on this website.

The current version of the data is version 2. It has been updated on March 26th 2019 UTC with some minor adjustments that affect the order of impressions and prices and the frequency of context descriptions.

Timeline top

Note: the timeline is subject to slight modifications.

When? What?
March 2019 Dataset Release & RecSys Challenge starts The website will go live on March 05.
June 30, 2019 RecSys Challenge ends
Final submission due (11:59 PM in the UTC-12:00 time zone).
July 2019 Announcement of the final leaderboard and winners
Paper submission for RecSys Challenge Workshop
August 2019 Paper Acceptance Notifications
Camera-ready due for the accepted papers
September 16-20, 2019 Workshop will take place as part of the ACM RecSys conference in Copenhagen, Denmark.

Challenge Organizers top

Advisors top