Spatial analysis

Spatial analysis is the part of working with geographic data where you ask questions that only make sense because the data has a location. Not how many, but where, how clustered, how near, how reachable.

The methods split roughly into a few families. Proximity and reachability ask what can be reached from a point, which is where catchment areas and travel times sit. Overlay asks what falls inside what, which is how you combine a flood zone with a building layer. Aggregation summarises many points into areas, so thousands of individual records become a pattern you can see. Clustering asks whether the pattern is real or the kind of grouping you would expect by chance.

The practical value is that spatial patterns are usually invisible in a table. A dataset can show that provision is adequate on average while a map of the same dataset shows that it is concentrated in three neighbourhoods and absent from six others. The average was never wrong. It just was not the answer to the question anyone cared about.