User simulations for interactive search: evaluating personalized query suggestion

Abstract. In this paper, we address the question “what is the influence of user search behaviour on the effectiveness of personalized query suggestion?”. We implemented a method for query suggestion that generates candidate follow-up queries from the documents clicked by the user. This is a poten-tially effective method for query suggestion, but it heavily depends on user behaviour. We set up a series of experiments in which we simulate a large range of user session behaviour to investigate its influence. We found that query suggestion is not profitable for all user types. We identified a number of significant effects of user behaviour on session effectiveness. In general, it appears that there is extensive interplay between the examination behaviour, the term selection behaviour, the clicking behaviour and the query modifi-cation strategy. The results suggest that query suggestion strategies need to be adapted to specific user behaviours