Teevan is a specialist in search and information retrieval for Microsoft Research. In this paper, she addresses three topics that are central to effective search performance by the searcher (user) and effective product design by the product development team. The topics considered concern the relationship between the recall, recognition, and reuse of search results, in considering user performance during repeated search activity over a short number of days.

It is well known in the product design community that users bring with them perceptions of how search engines work--their own mental models; rightly or wrongly, these influence each user’s understanding of presented results. Teevan’s big contribution in this paper is that she illustrates key aspects of the search experience that must be maintained as consistent between different sessions of product interaction, in order to avoid confusion in the user experience. She also illustrates how some aspects of the search product and the way search works can be manipulated to benefit the user, without causing confusion. The key to this contribution is the identification, in the product, of structures that are remembered and structures that are not remembered.

The research is comprehensive, involving multiple studies that have been completed as part of this research project, with extensive testing, using hundreds of participants in very structured tests.

This is a great paper, though Teevan has already identified that a more longitudinal study would enhance our understanding.