The Cognition of Scale in Human Search Problems and Wayfinding Strategy Thomas J. Pingel Northern Illinois University Victor R. Schinazi ETH Zürich Annual Meeting of the Association of American Geographers, Tampa, FL, April 11, Session: Cognition, Behavior, and Representation I - Spatial Cognition and Wayfinding Behavior

Strategy What is strategy? Distinctions between – strategic and systematic – search and memorization strategy – strategy and performance Predictors of spatial strategy – Environmental spatial ability – Personality factors – Scale

How do the strategies that an individual uses to explore a room affect his or her cognitive map? Strategy type changed between trials, and overall time was lower. But, no clear improvement in object location recall between trials. Tellevik (1992)

As measured by object learning performance, which strategies are most effective? Good performers had twice the number of object-to-object visits. Gridline search strategies were almost never used. Poor performers were observed to use perimeter strategies nearly twice as often, but verbally reported using fewer. Gaunet and Thinus-Blanc (1996) found strategy not related to IQ. Hill et al. (1993)

How would sighted individuals solve it? Vision helps coordinate search, but an introduced lack of vision increases novelty and difficulty.

Method Find and remember the locations of four invisible objects, whose positions are marked only with audio cues. 3 Scales of Search – 20 m 2, 250 m 2, 1000m 2 Position tracked with – Laser-based system indoors – high-grade GPS outdoors Afterward, indicate position via compass and sketch Self-report based measures of environmental spatial ability and strategic disposition 48 total participants

Scale and Multiple Psychologies of Space Montello (1993) Figural – smaller than the body – Directly perceived, no locomotion required Vista – larger than the body – directly perceived, no locomotion required Environmental – larger than the body – directly perceived, locomotion required Geographical – much larger than the body – learned via maps or models

Strategy Types Search strategy; human-coded (3 independent judges, 2/3 agree) – Scanline A series of sequential, parallel transects – Perimeter A continuous search of the perimeter of the space Task strategy; machine-coded (based on track data) – Search (%) Movement to an object not previously found – Localization (%) Movement to finely fix the position of an object – Reinforcement (%) Direct movement between previously found objects

Larger spaces require longer (total) searches. Spearman’s r(48) = 0.47; p <.001

The composition of the search changes with scale; significantly so for search (p <.001) and reinforcement (p <.001).

Type of search strategy changes with scale, significantly so for scanline (p=.01) and perimeter (p<.001)

Index measures as predictors SBSOD predicts – Total time and distance – Object location recall (via model placement) – But not Search or Task strategy Strategic Disposition Index predicts – Object location recall (via model placement) – But not Total time and distance Search or Task strategy

Strategy and performance Controlling for scale, type of search strategy (scanline, perimeter) does not impact: – Pointing / placement performance – Total search distance or time – Explicit search distance or time

Strategy ≠ systematic search. Strategy describes methods applied to a goal. The goal is not (or may not be) to reduce mean search distance (or time). It may be to solve the problem within an {acceptable, predictable, satisfactory} level of cost.

Mean time is higher for systematic searchers. But, variability tends to be lower. Systematic searching may be related to risk aversion.

Conclusions Strategy is not equivalent to either systematic search or performance. Scale is a strong determinant of both search and task strategy. The difference in strategy observable at vista scale indicates that refinements to Montello’s (1993) typology may be needed.

Acknowledgments NIU students Ben Maloney and Stacey Terlep ETH Zurich interns Dario Meloni and Carina Hoppenz University of California Transportation Center for grant support Gaunet, F., & Thinus-Blanc, C. (1996). Early-blind subjects’ spatial abilities in the locomotor space: Exploratory strategies and reaction-to-change performance. Perception, 25(8), Hegarty, M., Richardson, A. E., Montello, D. R., Lovelace, K., & Subbiah, I. (2002). Development of a Self-Report Measure of Environmental Spatial Ability. Intelligence, 30, Hill, E.W., Rieser, J.J., Hill, M.M., Hill, M., Halpin, J., & Halpin, R. (1993). How persons with visual impairments explore novel spaces: strategies of good and poor performers. Journal of Visual Impairment and Blindness, 87(8), Montello, D. R. (1993). Scale and multiple psychologies of space. In A. U. Frank, & I. Campari (Eds.), Spatial information theory: a theoretical basis for GIS. Proceedings of COSIT ’93. Lecture Notes in Computer Science, vol. 716 ( pp. 312–321). Berlin: Springer-Verlag. Pingel, T. J. (2012). Characterizing the Role of Strategic Disposition and Orientation to Risk in Wayfinding. Transportation Research Part F: Traffic Psychology and Behaviour, 15(4), Tellevik, J.M. (1992). Influence of spatial exploration patterns of cognitive mapping by blindfolded sighted persons. Journal of Visual Impairment & Blindness, 92, References

Sex Differences of Index Measures Self-report of environmental spatial ability was higher for men (M=6.0) than women (M=5.5) – Effect size (Cohen’s d=0.5) consistent with the literature (Hegarty et al., 2006) Self-report of strategic disposition was higher for men (M=5.4) than women (M=3.9) – Effect size (d=1.1) Meta-analysis across several studies suggests these are linked – r(134) = 0.48, p<.001 – Difference in this male/sdi population with respect to norm

30 participants – congenitally blind – adventitiously blind – blindfolded sighted Explore, then, on a later trial, detect a change to the layout of objects Congenitally blind performed worse – Used cyclical visits Adventitiously blind and blindfolded sighted – Used back-and-forth visits Performance and strategy not linked to IQ Gaunet and Thinus-Blanc (1996)

The Santa Barbara Sense of Direction Scale (Hegarty et al., 2002) 1. I am very good at giving directions. 2. I have a poor memory for where I left things. 3. I am very good at judging distances. 4. My "sense of direction" is very good. 5. I tend to think of my environment in terms of cardinal directions (N, S, E, W). 6. I very easily get lost in a new city. 7. I enjoy reading maps. 8. I have trouble understanding directions. 9. I am very good at reading maps. 10. I don't remember routes very well while riding as a passenger in a car. 11. I don't enjoy giving directions. 12. It's not important to me to know where I am. 13. I usually let someone else do the navigational planning for long trips. 14. I can usually remember a new route after I have traveled it only once. 15. I don't have a very good "mental map" of my environment. Correlates well with – Pointing to landmarks at a variety of scales – Blindfolded updating – Learning environments from Virtual Environments and video But not – Vandenberg and Kuse mental rotation test – Embedded figures test

The Strategic Disposition Index (Pingel. 2012) Frequency of and affinity for strategic thinking. Able to externalize or explain strategy. Correlated to preference for orientation and route-based wayfinding strategies.

Sex effects on strategy selection Controlling for scale, no sex effect for – Search strategy: scanline, perimeter, ISS – Task strategy: search, localize, reinforce – Overall search performance: time & distance – Object learning performance: pointing & placement

Vision and Search Strategy