Fading Away: Dilution and User Behaviour

Paul Thomas
CSIRO and Australian National University, Canberra, Australia

Falk Scholer
School of Computer Science and Information Technology, RMIT University, Victoria 3001, Australia.

Alistair Moffat
Department of Computing and Information Systems, The University of Melbourne, Victoria 3010, Australia.


Proc. 3rd European Wrkshp. on Human-Computer Interaction and Information Retrieval, Dublin, July 2013, pages 3-6.


When faced with a poor set of document summaries on the first page of returned search results, a user may respond in various ways: by proceeding on to the next page of results; by entering another query; by switching to another service; or by abandoning their search. We analyse this aspect of searcher behaviour using a commercial search system, comparing a deliberately degraded system to the original one. Our results demonstrate that searchers naturally avoid selecting poor results as answers given the degraded system; however, the depth of the ranking that they view, their query reformulation rate, and the amount of time required to complete search tasks, are all remarkably unchanged.

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