You can argue that taking information and rendering it visually belongs inside the A of analysis. We are classifying what John Snow achieved as a type of thought experiment . By plotting data he gained insight saving thousands of lives .
Biography John Snow (15 March 1813 – 16 June 1858) was an English physician and a leader in the adoption of anaesthesia and medical hygiene. He is considered one of the fathers of modern epidemiology, in part because of his work in tracing the source of a cholera outbreak in Soho, London, in 1854. His findings inspired fundamental changes in the water and waste systems of London, leading to similar changes in other cities . Resulting in a significant improvement in general public health around the world .
It is from is this map – plotting the outbreak of cholera cases, that John Snow had his eureka moment his insight that cholera was spread from a single source .# As you can see the cases radiate outwards from the epicentre : a water pump
Modern policing makes extensive use of maps .When combined with big data plotting data as maps simplifies complex information. Revealing hidden patterns . Data maps make excellent prediction tools especially when you are dealing with large data sets .