Revisiting John Snow's Cholera Map
A Data Visualisation Case Study for Statistical Education
Keywords:
Visualisation, Exploratory Data Analysis, John Snow, Cholera, Spatial DataAbstract
Data visualisation is a fundamental tool in statistical analysis, enabling the identification of patterns and relationships that might otherwise remain hidden in raw data. One of the most famous historical examples is John Snow's 1854 cholera map, which demonstrated the spatial clustering of cholera cases around a contaminated water pump in London. This study explores how Snow's visualisation can be effectively incorporated into statistics education as an interactive case study. Revisiting Snow’s cholera map in 2025 provides a powerful bridge between foundational epidemiological reasoning and modern statistical practice. It offers students an intuitive, historically grounded pathway into spatial thinking and data visualisation using tools like R. Using R, we outline the steps involved in reproducing Snow's cholera map, demonstrating geospatial data manipulation, visualisation techniques, and spatial analysis. We discuss the pedagogical benefits of historical case studies in statistics courses, emphasising their role in fostering curiosity, critical thinking, and technical proficiency. Additionally, we explore how these methods can be extended beyond epidemiology to applications in public health, urban analytics and environmental science. By integrating historical datasets with modern computational tools, educators can create engaging, hands-on learning experiences that reinforce core statistical principles while illustrating the real-world impact of data analysis.
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