An end-user evaluation to analyze the effectiveness of cartograms for mapping relative non-motorized accessibility

Abstract

Relative accessibility is a widely studied approach that recognizes access to major locations as subjective and shaped by individual circumstances (e.g., individual preferences, habits, and cultural norms). One missing element in the knowledge base is how relative accessibility can be effectively mapped for decision-making. To fill the research gap, this paper evaluates whether cartograms are an appropriate tool for mapping relative accessibility, taking the city of Zaragoza, Spain as a case study. The research design included three phases: (i) elaboration of grid-based maps on relative non-motorized accessibility; (ii) elaboration of cartograms on relative non-motorized accessibility; (iii) an end-user evaluation with 30 local practitioners to analyze the effectiveness of cartograms to map relative accessibility compared to grid-based maps. Participants signaled that diffusion-based cartograms could be complementary to grid-based maps, providing better visualization of spatial dissimilarity patterns of accessibility between population groups. However, participants noted greater difficulty in identifying Dorling cartograms as an effective technique for mapping relative accessibility. The paper closes with a review of the strengths and weaknesses of the potential application of these visualization techniques in the field of accessibility planning.