Overview of the CLEF Dynamic Search Evaluation Lab 2018.

In this paper we provide an overview of the CLEF 2018 Dynamic Search Lab. The lab ran for the first time in 2017 as a workshop. The outcomes of the workshop were used to define the tasks of this year's evaluation lab. The lab strives to answer one key question: how can we evaluate, and consequently build, dynamic search algorithms? Unlike static search algorithms, which consider user request's independently, and consequently do not adapt their ranking with respect to the user's sequence of interactions and the user's end goal, dynamic search algorithms try to infer the user's intentions based on their interactions and adapt their ranking accordingly. Session personalization, contextual search, conversational search, dialog systems are some examples of dynamic search. Herein, we describe the overall objectives of the CLEF 2018 Dynamic Search Lab, the resources created, and the evaluation methodology designed.