Geography Reference
In-Depth Information
of this reading process could have an influence on the users
cognitive load
(Harrower
2007
; Bunch and Lloyd
2006
). Due to the different characteristics of
screens and paper, the same information is displayed differently: resolution, colour
display, etc. This could cause differences in how the users read the information on
the map. These differences could have an influence on the users
'
perceived level of
satisfaction and thus preference towards a certain medium. Therefore, it is impor-
tant to study these processes to be able to explain the findings in previous research.
'
Extending the Research: Eye Tracking
Processing a visual scene, such as a map, is based on the visual input on the one
hand (bottom-up processing) and the user
s background knowledge (top-down
processing) on the other hand (e.g. MacEachren
1995
). Wolfe (
1994
) described a
model (or set of rules) that predict where a user will focus his attention during a
visual search. Recent findings in the field of change blindness also stressed the
importance of attention to be able to interpret a visual scene (Rensink
2002
; Simons
and Ambinder
2005
).
Using eye tracking, the users
'
eye movements are registered: where a user is
looking (Point of Regard, POR), but also how long and how often. These latter
metrics can give insights in the user
'
s cognitive processes while trying to interpret
the visual content. When studying the interpretation process, fixations are most
important. These define the time intervals when and locations where a user is
processing the visual content. Saccades are fast eye movements between fixations
during which no information is processed. More fixations at a certain location
indicates that the user
'
s attention is attracted by something at this location. Longer
fixations can indicate that the user finds it difficult to interpret the content. These
and many other eye movement metrics have been studied in previous research,
including their potential
'
s cognitive processes (Holmqvist
et al.
2011
). It is beyond the scope of this paper to discuss them all. A good
overview can be found in a number of topics and journal articles: Duchowski
(
2007
), Holmqvist et al. (
2011
), Goldberg et al. (
2002
), Jacob and Karn (
2003
),
Poole and Ball (
2006
), Rayner (
1998
), among others.
Paper maps have already been included in eye tracking studies in the 1970s
(e.g. Dobson
1977
; Jenks
1973
) and the 1980s (e.g. Castner and Eastman
1984
,
1985
; Steinke
1987
). The stimuli at that time were mainly dot maps. The authors
concluded that, although the method was applicable, no new knowledge could be
derived. Consequently, the method almost disappeared in cartographic research
afterwards. In the beginning of 2000 however, a mobile (head mounted) eye tracker
was successfully used by Brodersen et al. (
2001
) to study the effectiveness of a new
symbology for the printed topographic maps in Denmark. Nevertheless, no com-
parison was made with digital maps.
Recently, a rise is noticed in the application of the method in cartographic user
research (e.g. ¸¨ ltekin et al.
2009
; Fabrikant et al.
2008
; Kiefer et al.
2014
; Ooms
link to the user
'
