Does it correlate?
In this part, you will try to explore spatial autocorrelation on your own.
Scottish Index of Multiple Deprivation again
In the exercise on pandas
, you have worked with the Scottish Index of Multiple Deprivation (SIMD). Since you learned how to work with spatial data later, there was no geometry assigned. That will change today.
- Download the ESRI Shapefile version of the Scottish Index of Multiple Deprivation 2020 from this link.
- Read it as a
GeoDataFrame
and assign a column you think would be the best as an index.
- Filter the data to work only with Glasgow.
- Create contiguity weights based on the reduced dataset.
Global spatial autocorrelation
With the data prepared like this:
Join Counts
- Create a binary variable from
"Rankv2"
encoding areas with rank above city-wide mean. - Measure Join Counts statistic on your new variable.
- What conclusions can you reach from the Join Counts?
Moran’s \(I\)
- Visualise the main
"Rankv2"
with a Moran Plot - Calculate Moran’s \(I\)
- What conclusions can you reach from the Moran Plot and Moran’s I? What’s the main spatial pattern? Does it agree with Join counts?
Local spatial autocorrelation
Now that you have a good sense of the overall pattern in the SIMD dataset, let’s move to the local scale:
- Calculate LISA statistics for the areas
- Make a map of significant clusters at the 5%
- Can you identify hotspots or coldspots? If so, what do they mean? What about spatial outliers?
Warning
The last action is a bit more sophisticated, put all your brain power into it and you’ll achieve it!
- Create cluster maps for significance levels 1% and 10%; compare them with the one we obtained. What are the main changes? Why?
- Create a single map that combines all three significance levels and changes the alpha to distinguish them.
- Can you create both interactive and static versions of those maps?
Acknowledgements
This section is derived from A Course on Geographic Data Science by Arribas-Bel (2019), licensed under CC-BY-SA 4.0. The text was slightly adapted to accommodate a different dataset and the inclusion of Join counts.
References
Arribas-Bel, Dani. 2019. “A Course on Geographic Data Science.” The Journal of Open Source Education 2 (14). https://doi.org/10.21105/jose.00042.