Projecte realitzat en el marc d’un programa de mobilitat amb la University of Helsinki. Faculty of Science. Department of Computer ScienceThis thesis goes further in the study of implicit indicators used to infer interest in documents for information retrieval tasks. We study the behavior of two different categories of implicit indicators: fixation-derived features and physiology (pupil size, electrodermal activity). Based on the limited
number of participants at our disposal we study how these measures react when addressing
documents at three different reading rates. Most of the fixation-derived features are reported to
differ significantly when reading at different speeds. Furthermore, the ability of pupil size and
electrodermal activity to indicate perceived relevance is found intrinsically dependent on speed of
reading. That is, when users read at comfortable reading speed, these measures are found to be
able to correctly discriminate relevance judgments, but fail when increasing the addressed speed of
reading. Therefore, the outcomes of this thesis strongly suggest to take into account reading speed when designing highly adaptive information retrieval systems
