An empirical evaluation of three elevation change symbolization methods along routes in bicycle maps

Elevation change is critical for choosing a route when bicycling. We detail an empirical study in which we comparatively evaluated three linear symbolization types (color hue, color-coded arrows, and elevation profiles) to depict elevation change in bicycle maps for two common bicycle route planning tasks: relative height detection and slope identification. Participants performed most accurately with the color-coded arrows for relative height detection tasks, whereas symbolization did not significantly influence map-use performance for slope identification. Participants preferred the elevation profile, in spite of their lowest performance with this method overall. Our rare empirical findings offer much needed new insights into the function and appropriateness of common elevation symbolization methods, specifically to identify elevation change in bicycle route planning tasks in urban areas where map display real estate is already very limited.