1-III_am

[27] Identifying the map representation in crime maps and its effect on viewer's perception

- Psychological experiment using multiple maps with different color schemes and classification methods -

○Mayuko Yamane¹, Mamoru Amemiya², Mayu Shirakawa³, Tomoya Ohyama², Takahito Shimada⁴ (1. University of Tsukuba, 2. University of Tsukuba , 3. Nihon University, 4. National research institute of police science)

Keywords:Crime map, Visual perception, Map design, Experiment, Hotspot

It is recommended to adopt kernel density maps (KD maps) to crime mapping on Japanese prefectual police's websites. Although visual impression of maps differs dependeing on the combination of color scheme and classification method, the appropriate combination has not been clarified. In this research, we surveyed the map representation in crime maps of the prefectual polices in Japan and identified the effects of the color scheme / classification method of KD maps on the location estimation of crime hotspots and the estimation of crime occurrence frequency by two experiments. As a result of the experiments, it was found that estimation of crime hotspots would be inaccurate and estimation of frequency of crime would be overestimated in the case of using the quantile classification. Based on the result, we discussed matters to be noted when designing crime maps using kernel density estimation.