Package index • sfhotspot

Analysing hotspots

Tools for analysing hotspots.

hotspot_count(): Count points in cells in a two-dimensional grid
hotspot_change(): Identify change in hotspots over time
hotspot_kde(): Estimate two-dimensional kernel density of points
hotspot_dual_kde(): Estimate the relationship between the kernel density of two layers of points
hotspot_gistar(): Identify significant spatial clusters of points
hotspot_dbscan(): Identify hotspots using DBSCAN
hotspot_classify(): Classify hot-spots
hotspot_classify_params(): Control the parameters used to classify hotspots

Data wrangling

Tools for working with data that is used to identify hotspots. Most data wrangling is done automatically by the analysis functions listed above, but you can use the functions below to control in more detail how this is done.

hotspot_clip(): Extract spatial features inside a polygon
hotspot_grid(): Create either a rectangular or hexagonal two-dimensional grid
st_transform_auto(): Toggle between lon/lat and UTM co-ordinates

Plotting results

hotspot_map() creates complete maps, while hotspot_layer() creates layers that can be combined with other ggplot2 layers. The autoplot() methods automatically produce charts tailored to the results from the hotspot_*() family of functions. hotspot_isoband() generalises the polygons produced by the hotspot-analysis functions into polygons, which can sometimes be preferable for plotting.

hotspot_map(): Create an automatic map
hotspot_layer(): Create a ggplot layer from hotspot results
hotspot_isoband(): Convert a hotspot grid to isobands
autoplot(<hspt_c>) autolayer(<hspt_c>) hotspot_map(<hspt_c>): Plot map of hotspot classifications
autoplot(<hspt_d>) autolayer(<hspt_d>) hotspot_map(<hspt_d>): Plot map of changes in grid counts
autoplot(<hspt_dk>) autolayer(<hspt_dk>) hotspot_map(<hspt_dk>): Plot map of dual kernel-density values
autoplot(<hspt_g>) autolayer(<hspt_g>) hotspot_map(<hspt_g>): Plot map of Getis-Ord Gi* results
autoplot(<hspt_ib>) autolayer(<hspt_ib>) hotspot_map(<hspt_ib>): Plot isobands
autoplot(<hspt_k>) autolayer(<hspt_k>) hotspot_map(<hspt_k>): Plot map of kernel-density values
autoplot(<hspt_n>) autolayer(<hspt_n>) hotspot_map(<hspt_n>): Plot map of grid counts
autoplot(<hspt_s>) autolayer(<hspt_s>) hotspot_map(<hspt_s>): Plot DBSCAN hotspot clusters

Sample data

Sample data that can be used with the functions in this package.

memphis_population: Populations of census blocks in Memphis in 2020
memphis_precincts: Memphis Police Department Precincts
memphis_robberies: Personal robberies in Memphis in 2019
memphis_robberies_jan: Personal robberies in Memphis in January 2019