Sharing Cartographic Knowledge with the Crowd: on the Complexity of Cartographic Rules
ISBN 978-85-88783-11-9
Authors
1Panchaud, N.H.; 2Iosifescu Enescu, I.; 3Hurni, L.
1ETH ZURICH, INSTITUTE OF CARTOGRAPHY AND GEOINFORMATION Email: nadia.panchaud@ethz.ch
2ETH ZURICH, INSTITUTE OF CARTOGRAPHY AND GEOINFORMATION Email: iosifescu@ethz.ch
3ETH ZURICH, INSTITUTE OF CARTOGRAPHY AND GEOINFORMATION Email: lhurni@ethz.ch
Abstract
Cartographic knowledge consists of principles, expertise, conventions and rules of thumb that trained cartographers learn how to use and understand. As cartography enters a new era with the advent of Web 2.0, enabling neogeography and crowdsourcing, the map-making process opened up to a wider audience, which thus is often referred to as neogeographers. These cartographic-laypersons create and modify maps online by combining various resources and cartographic tools available. However, the integration of cartographic principles for the visualization and combination of existing spatial data within geoportals trails behind in its transition to Webmapping 2.0. This integration requires the formalization of cartographic principles and heuristics. For this purpose, we need to have a grasp of the complexity of the cartographic principles. This is realized by looking at the numbers and types of parameters as well as the numbers of relation be-tween them that are required for the formalization and integration of each principle. We discuss here two cartographic principles based on their complexity. First, we look at the formalization of the drawing order of layers and second at the visual hierarchy. The first principle can be formalized by analyzing pair-wisely the layers composing the map and determining whether the order should be reversed or not. The realm of acceptable solutions is limited. The second one involves adjusting the color scheme and contrast between background and foreground information to support the visual hierarchy and not only requires more parameters but also these parameters are more tightly interwoven. Additionally, the realm of solutions is vaster that the few acceptable configurations of layers. Thus, the formalization and integration of those two principles should follow different paths. The first one might require little user input, because it gathers information from the state of the geoportal, whereas the second one might require a more important user involvement in fine-tuning the process. As a conclusion, we show that the type of implementation best suited to share cartographic knowledge on a geoportal can differ from one principle to another due to their complexity and solution realm.