What this lesson teaches
I can use regions, spatial patterns and spatial associations to explain how locations in a neighbourhood relate.
Syllabus K335, Topic 1.1, Key Question 3. What is the relationship between locations in a neighbourhood?
Make a guess
A map shows that most clinics in a town lie near MRT stations. What does the map prove?
- Only that the two tend to occur together.
- Patients always travel to clinics by MRT.
- Clinics are spread randomly across the town.
- The stations caused the clinics to open there.
Show the answer
Only that the two tend to occur together.
A map shows a spatial association, not its cause. The station, new housing or something else may explain it, so more evidence is needed.
First describe where things are, then compare them with other features, and only then look for reasons.
A region is an area grouped by something shared, such as land use or identity. A clinic's sphere of influence is the area its patients come from. It can overlap with other clinics' areas.
A spatial pattern describes how one type of feature is arranged. It is not random. Shops may cluster, trees may form a line, and bus stops may be evenly spaced. Name the feature, describe the pattern, give a location and note any exceptions.
A spatial association is when two types of feature tend to occur together. For example, clinics may lie near MRT stations. This suggests a link, but does not prove the cause. The station may have attracted clinics, or both may have followed new housing. Opening dates and travel surveys can test this.
Sort these
Is each statement a spatial pattern (how one feature is arranged) or a spatial association (two features occurring together)?
Groups: Spatial pattern, Spatial association.
- Bus stops along the avenue are evenly spaced.
- Playgrounds tend to lie close to clusters of homes.
- Trees form a line along both sides of the main road.
- Clinics tend to lie near MRT stations.
- Food stalls cluster around the entrance of the market.
- Streets that flood often tend to be the low-lying ones.
Show the answer
Spatial pattern
- Bus stops along the avenue are evenly spaced. Evenly spaced describes the arrangement of one feature, the bus stops, so it is a pattern.
- Trees form a line along both sides of the main road. Only the trees are described. A line is one way a single feature can be arranged.
- Food stalls cluster around the entrance of the market. It describes how one type of feature, food stalls, is arranged. No second feature is compared.
Spatial association
- Playgrounds tend to lie close to clusters of homes. It links two features, playgrounds and homes, that are found together. It does not yet explain why.
- Clinics tend to lie near MRT stations. Two different features, clinics and stations, tend to occur together. That is an association.
- Streets that flood often tend to be the low-lying ones. Flooding and low ground are two features occurring together, so this is an association to investigate.
- Sphere of influence
- The area a service draws people from.
- Spatial pattern
- How one feature is arranged: clusters, lines or regular gaps.
- Spatial association
- Two features tend to occur together; not proof of cause.
Step by step
Describe
Name the feature, its arrangement, a place and an exception.
Compare
Check if a second feature tends to occur with it.
Investigate
Collect evidence before explaining why.
Real examples to use
John Snow's cholera map, London, 1854
Snow mapped cholera deaths in Soho and found they clustered around one water pump on Broad Street. He used this association, with other evidence about who drank the water, to argue that cholera spread through water. A cluster alone did not prove the cause.
Worked example: Close by is not proof
In a made-up town, four of five clinics are within 300 m of a station. That is a spatial association. If interviews show many patients arrive by train, easy rail access becomes a stronger explanation.
Watch out for this
Two features close together must have caused each other.
They may share another cause or be close by chance. Check the evidence first.
Check your understanding
Which statement describes a spatial association?
- Playgrounds tend to lie close to clusters of homes in the estate.
- Shops form a straight line along the eastern road of the estate.
- The playgrounds were built because the households asked for them.
Show the answer
Playgrounds tend to lie close to clusters of homes in the estate.
Yes. It compares where two features occur.
Check your understanding
Clinics are often found near MRT stations. What can you conclude?
- Stations cause clinics to open nearby, because the link repeats in many towns.
- The two features are randomly arranged, and the closeness is chance.
- The two are associated, but the link does not prove a cause.
Show the answer
The two are associated, but the link does not prove a cause.
Opening dates or travel surveys could test why.