Geography Reference
In-Depth Information
eye movements on a
large screen (at close viewing distance), not all trials could be included in the
analyses (missing data, large deviations, etc.). Still, sufficient data was gathered
(at least 20 persons per trial) to be able to conduct statistical analyses. The selection
of suitable data is discussed in detail
Due to some problems with registering the participants
'
in section “Creating the Gridded
Visualisation”.
Stimuli
Twelve different stimuli were used in the user study, based on six different map
sheets of topographic maps on 1:10,000 of the Belgian national mapping agency
(IGN/NGI Belgium): Assesse 54/1 N, Ciney (Est) 45/2 S, Daussois 52/8 S, Leignon
54/6 N, Onhaye 53/7 N and Walcourt 52/8 N. These six map sheets (see Fig.
1a
)
were visualised on a screen (digital medium) or on paper. Each participant will
perform a task (see section “Task”) on three digital and three paper maps. Using
two similar user groups with different stimuli (switching between paper and digital
map sheets) avoids a learning effect and keeps the duration of the user test limited
(as this could result in distorted measurements due to a diminished level of
concentration or fatigue by the participant).
The selection of these six map sheets was based on a number of criteria. First, it
should be unlikely that the participants knew the region by heart. All participants
lived in the northern part of Belgium and, therefore, the selected regions are located
in the southern part. Furthermore, the participants had to indicated in a post-study
questionnaire if they were familiar with one of the depicted regions (which would
then be removed from the results for that participant). Second, the type and number
of map objects should be limited and similarly distributed across the six map sheets.
As a consequence, the selected map sheets consist mainly of some major roads, a
small number of villages surrounded by meadows, fields and forests. Third, the
number of toponyms, their hierarchical classifications and their distributions should
be similar for all stimuli.
The aim of the study is to investigate the potential difference in the users
'
attentive behaviour while performing a task on two maps, between which the
medium (screen or paper) is the only difference. Therefore, all stimuli are presented
with exactly the same dimensions and on exactly the same location. Furthermore,
only the map page is presented to the participant, without the title, legend, scale bar,
meta data, etc. as this could distract the user. The dimensions correspond with these
of the original map sheet (82.5
52.7 cm). The digital maps have a resolution of
125 dpi and were visualised on a TV screen (see section “Apparatus and Set-Up”
for more details). The corresponding paper maps were printed at a resolution of
250 dpi.
In order to be able to compare the results between the two user groups, the six
regions were displayed to all participants. The only difference was the medium with
which the maps was displayed. While one saw a stimulus on the paper medium, the
