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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>The Impact of Environmental Qualities and Individual Differences on Spatial Orientation in a Mobile Context</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Rui Li</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Alexander Klippel</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Lynn S. Liben</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Adam E. Christensen</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Geography and GeoVISTA Center</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Department of Psychology The Pennsylvania State University</institution>
          ,
          <addr-line>University Park, PA 16802</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>To contribute to cognitive engineering for mobile users, we propose that mobility itself, the environment, and individual differences all have to be incorporated into a unified framework. To make this argument, we present both a position statement and results from a behavioral study. Forty participants were taken individually to 12 locations on different floors in a library where they estimated their location and orientation on a map. Participants were randomly assigned to perform these tasks under one of two mobility conditions-either being required to stand in a single location (static) or being permitted to move before responding (active). Locations in the library were characterized using space syntax measures and individual differences were assessed using a battery of established tasks. Results show that mobility, environmental qualities, and individual differences all affect performance but that overall active exploration results in better performance. Through establishing this unified framework our research addresses fundamental questions of what it means-from a cognitive perspective-to be mobile.</p>
      </abstract>
      <kwd-group>
        <kwd>mobility</kwd>
        <kwd>indoor environment</kwd>
        <kwd>spatial skills</kwd>
        <kwd>spatial orientation</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        The use of mobile devices has created a new context for wayfinding, which is
different from wayfinding experiences that are associated with you-are-here (YAH)
maps. Instead of consulting pre-installed navigational services such as a YAH map
posted at a particular spot to learn where one is located, individuals using mobile
devices can receive on-the-go information of their current location while moving in
the environment. Studies have shown, however, that using mobile devices—in
comparison to using traditional maps or direct exploration—results in longer traveled
distances, longer travel times, and reduced accuracy in estimating directions [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
Acquisition of spatial knowledge and wayfinding are complex tasks. In this article we
focus on three factors that potentially influence wayfinding success in a mobile
context: mobility, environmental qualities, and individual differences.
      </p>
      <p>First, mobile devices obviously allow users to be mobile and receive on-the-go
information. The acquisition of spatial knowledge is thus not restricted to the user’s
current location. In the present article we operationalize a narrow meaning of being
mobile and contrast two conditions: static indicates situations in which individuals are
required to stay at their current location once they have been asked to locate
themselves and indicate their orientation on a map. In contrast, active indicates
situations in which individuals are permitted to move around before they have to do
the same tasks.</p>
      <p>
        Second, qualities of environments are potentially correlated with wayfinding
performance. Space syntax research has developed methods to quantitatively
characterize environments. Methods such as visibility graph analysis (VGA) [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], axial
map [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], and inter connection density (ICD) [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] have been used in studies relating
environmental qualities to wayfinding performance (see examples [
        <xref ref-type="bibr" rid="ref5 ref6 ref7">5-7</xref>
        ]; a fuller
review and introduction to these methods can be found in [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]). Complementing these
earlier studies, we introduce global and local measures of environmental qualities to
incorporate the critical concepts of spatial homogeneity and spatial heterogeneity into
our framework. Details on both global and local measures are introduced in the
methods section.
      </p>
      <p>
        Third, individual differences also influence wayfinding performance. Individuals
vary markedly in their measured spatial skills [
        <xref ref-type="bibr" rid="ref10 ref11 ref9">9-11</xref>
        ]. Studies have demonstrated an
association between individual differences and performance of spatial orientation (see
[
        <xref ref-type="bibr" rid="ref12 ref13 ref14">12-14</xref>
        ]). Here we adopted similar methods used by Liben and collaborators [
        <xref ref-type="bibr" rid="ref12 ref13 ref14">12-14</xref>
        ]
to differentiate individuals regarding their spatial skills.
      </p>
      <p>
        We chose an indoor environment in the present study given the rising interest in
indoor navigation. To name just a few illustrative studies, Worboys and collaborators
[
        <xref ref-type="bibr" rid="ref15 ref16">15, 16</xref>
        ] used bigraphs to model both outdoor and indoor environments; Giudice and
collaborators [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] adopted an ontological perspective to address data models and
functional models of both outdoor and indoor spaces; Richter and collaborators [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ]
address the hierarchical representation of indoor spaces.
      </p>
      <p>In sum, the goal of the current study was to understand how spatial orientation is
affected by different conditions of mobility; by different environmental qualities as
measured by space syntax methods; and by individual differences as assessed by
paper-and-pencil spatial tasks.
2
2.1</p>
    </sec>
    <sec id="sec-2">
      <title>Methods</title>
      <sec id="sec-2-1">
        <title>Participants</title>
        <p>Forty college students recruited through a psychology subject pool were randomly
assigned to one of two conditions, specifically either static (11 males and 9 females,
M = 18.8 years, SD = 0.83) or active (5 males and 15 females, M =18.8 years, SD =
0.81). Participants received extra course credit for participation.
2.2</p>
      </sec>
      <sec id="sec-2-2">
        <title>Environment</title>
        <p>
          We selected two floors in the Central Stacks and Paterno Library within the main
library on our campus (see Figure 1) because they differ with respect to their
environmental qualities. The library has been anecdotally referred to as one of the
most difficult buildings on campus in which to find one’s way. We used VGA [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ],
axial map [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ], and ICD [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ] to characterize visibility, connectivity, and layout
complexity of this environment, respectively. A global measure was calculated across
each entire floor using each method. For the 12 locations (6 in the Central Stacks, 6 in
the Paterno Library) that we selected for orientation tasks, we also calculated local
measures, making sure to include an even combination of low and high values (see
Figure 2). As the global ICD is negatively correlated with global VGA and global
connectivity, the term “high global” as used in this article actually indicates low
global values for ICD. More specifically, the 12 locations were divided into four
different categories depending on their global and local values: low global/low local
(locations 1, 2, 3), low global/high local (locations 4, 5, 6), high global/low local
(locations 8, 10, 11), and high global/high local (locations 7, 9, 12). For example,
location 1, 2, and 3, located in Central Stacks, had relatively higher values of local
visibility and connectivity but low global visibility and connectivity.
Participants were taken to one of the two floors in counterbalanced order. Within a
given floor, they were taken to the six locations in an individually randomized order.
The experimenter led participants to the floors using staircases. While participants
were standing at each target location facing a designated direction, the experimenter
asked participants to draw a dot or “x” on the map to indicate their location and then
to draw an arrow on the map to show their orientation. The map was a simple floor
plan showing the locations of book shelves and the basic geometry of the
environment. This floor plan was simplified based on map schematization described
by Meilinger and collaborators [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ]. Participants in the static condition were asked to
stand in place as they completed all tasks; participants in the active condition were
free to move around before they provided their answers. Location responses were
scored as correct if the mark was within the correct book shelf aisle and within a 10
mm radius scoring circle on the map. Orientation responses were scored as correct if
the arrow was facing the correct direction within a 22.5° margin of error on either
side.
        </p>
        <p>
          Pencil-and-paper spatial tests were given after all environmental tasks were
completed. Tasks included an untimed water level test (WLT), a 3 min mental
rotation test (MRT), and a 3 min paper folding test (PFT) which, respectively,
assessed spatial perception, mental rotation, and spatial visualization [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]. The scores
of MRT were chosen as a differentiating factor of spatial skills because mental
rotation has been shown to correlate with orientation performance in some earlier
studies [
          <xref ref-type="bibr" rid="ref20 ref21">20, 21</xref>
          ] and because it is a component of spatial skills that is virtually always
identified in factor analyses [
          <xref ref-type="bibr" rid="ref22 ref9">9, 22</xref>
          ]. All three tests are considered in our continuing
work on prediction models, which are not reported in this paper.
3
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Results</title>
      <p>Performance at the 12 locations in 4 categories (low global/low local, low global/high
local, high global/low local, and high global/high local) was analyzed with two
separate repeated measures analyses of variance: one with the number of correct
location responses (maximum = 3 in each category) and one with the number of
correct orientation responses (maximum = 3 in each category) as the dependent
measures. In both analyses, between-subjects variables were mobility condition (static
vs. active) and spatial skill (low vs. high). The latter division was based on a median
split using participants’ mental rotation scores. The two within-subjects factors were
high or low global and local space syntax values.
3.1.1</p>
      <sec id="sec-3-1">
        <title>Location estimations</title>
        <p>The analysis of location estimates revealed a three-way interaction among global
value, mobility, and spatial skill. As shown in Figure 3, participants in the static
condition performed significantly worse on low than high global locations (M =1.08,
SD = 1.70 vs. M =.75, SD = 1.11, respectively, maximum = 6.0), but these patterns
did not differ in relation to participants' spatial skills. In contrast, in the active
condition, performance varied with both environmental qualities and individual
differences: at low global locations, performance by low spatial participants was
significantly worse than by high spatial participants (M =.71, SD = 1.73 vs. M =1.69,
SD = 1.27, respectively, maximum = 6.0) whereas at high global locations,
performance did not differ in relation to participants' spatial skills (M =1.36, SD =
1.57 vs. M =1.54, SD = 1.16, respectively, maximum = 6.0). Subsumed by this
interaction was a main effect of global value, F(1, 36) = 5.81, p&lt; .05, with fewer
correct responses at locations with low than with high global values (M = .84, SD =
.78 vs. M =1.18, SD = .71, respectively, maximum = 6.0). The main effect of local
values was only marginal, F(1, 36) = 3.26, p = .083.</p>
        <sec id="sec-3-1-1">
          <title>Low spatial High spatial ) 2</title>
          <p>t
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        </sec>
        <sec id="sec-3-1-2">
          <title>Low global</title>
        </sec>
        <sec id="sec-3-1-3">
          <title>High global</title>
        </sec>
        <sec id="sec-3-1-4">
          <title>Low global</title>
        </sec>
        <sec id="sec-3-1-5">
          <title>High global</title>
          <p>Static</p>
          <p>Active
Also evident was a significant effect of mobility, F(1, 36) = 12.08, p&lt; .01.
Participants in the active condition had significantly more correct estimates than those
in the static condition, (M =5.65, SD =2.48 vs. M =2.65, SD =2.03, respectively,
maximum = 12.0). There was also a marginal effect of spatial skills on performance,
F(1, 36) = 3.68, p= .06.
3.1.2</p>
        </sec>
      </sec>
      <sec id="sec-3-2">
        <title>Orientation estimations</title>
        <p>The analysis of orientation estimates revealed a two-way interaction between global
and local values. When locations had low global values, orientation performance did
not differ between low and high local values (M =2.14, SD =1.00 vs. M =2.10, SD
=.95, respectively, maximum = 3.0). In contrast, when locations had high global
values, orientation accuracy was significantly worse at locations with low than with
high local values (M =1.40, SD =.97 vs. M =2.66, SD =.72, respectively, maximum =
3.0). Subsumed by the interaction was a significant main effect of local value, F(1,
36) = 29.13, p&lt; .01. Orientation accuracy was lower at locations with low than with
high local values (M =1.78, SD = .71 vs. M =2.38, SD = .72, respectively, maximum =
6.0).</p>
        <p>Also evident was the effect of mobility, F(1, 36) = 12.49, p&lt; .01. Participants in
the active condition provided more correct responses than in the static condition (M
=9.75, SD =1.55 vs. M =7.15, SD =2.87, respectively, maximum = 12.0).
4</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Discussion</title>
      <p>
        The mobility of a person is vital to the accuracy of locating and orientating oneself in
buildings. Earlier studies have suggested that active exploration results in
significantly better development of spatial knowledge [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ] [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ]. Similarly, our results
show that being mobile facilitates adults’ accuracy on both location and orientation
performance. This is an important insight potentially relevant to the design of
navigational services on mobile devices.
      </p>
      <p>
        Adults have difficulty locating or orientating themselves in indoor environments, a
finding that is similar to ones reported in wayfinding research in outdoor
environments [
        <xref ref-type="bibr" rid="ref12 ref14">12, 14</xref>
        ]. Environmental qualities and individual differences each affect
locating and orientating oneself in buildings, although their effects are intricate. The
environmental qualities obtained from space syntax that differentiate locations based
on their global and local values, are associated with performance. In the location task,
adults show less accurate performance in buildings with low global values than in
buildings with high global values. Additionally, performance is worse among adults
with poorer spatial skills. Relating the factor of mobility to the environment and
individual differences, our results show that adults with higher spatial skills benefit
more from being mobile than those with poorer spatial skills. In the orientation task,
adults have difficulty estimating orientation in a complex building. The local qualities
of locations such as their visibility do not seem to be the factor that has a major
impact. That is, when global values are low at locations, local values do not matter
further. When global values are high, however, local values significantly modify
performance.
5
      </p>
    </sec>
    <sec id="sec-5">
      <title>Conclusion</title>
      <p>
        Our study has addressed a core question relevant to an aspect of using mobile devices:
mobility itself. We strive for a holistic perspective on people’s performance in spatial
environments by establishing a framework which incorporates not only mobility, but
also environmental qualities and individual differences. In addition to supporting
findings from earlier studies that related characteristics of the environment to
individual wayfinding behaviors [
        <xref ref-type="bibr" rid="ref5 ref7">5, 7</xref>
        ], we demonstrated the influence of mobility,
environmental qualities, and individual differences on location and orientation
performance. Furthermore, we advanced the understanding of environmental qualities
and individual differences by using theories from spatial information science as well
as from classic cognitive psychology. In addition to the suggestion of Gunzelmann
and Anderson [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ] that features of location impact spatial orientation, we further
explored locations with respect to their global and local characteristics, a theoretical
construct well known in spatial analysis but not yet integrated into a science of
mobility for which it seems to be particularly relevant.
      </p>
      <sec id="sec-5-1">
        <title>Acknowledgement</title>
        <p>Research for this paper is based upon work supported by the National Science
Foundation under Grant No. 0948601. The views, opinions, and conclusions
contained in this document are those of the authors and should not be interpreted as
necessarily representing the official policies or endorsements, either expressed or
implied, of the National Science Foundation, or the U.S. Government.</p>
      </sec>
    </sec>
  </body>
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