Project 3, Part B: Mean Nearest Neighbor Distance Analysis

Mean Nearest Neighbor Distance Analysis for the Crime Patterns

Although nearest neighbor distance analysis on a point pattern is less commonly used now, the outputs generated can still be useful for assessing the distance between events.

The spatstat nearest neighbor function nndist.ppp() returns a list of all the nearest neighbor distances in the pattern.

For a quick statistical assessment, you can also compare the mean value to that expected for an IRP/CSR pattern of the same intensity.

Give this a try for one or more of the crime patterns. Are they clustered? Or evenly-spaced?

#Nearest Neighbour Analysis
nnd <-nndist.ppp(xhomicide)
hist(nnd)
summary(nnd)

mnnd <-mean(nnd)
exp_nnd <-(0.5/ sqrt(xhomicide$n / area.owin(Sbnd)))
mnnd / exp_nnd

Repeat this for the other crimes that you selected to analyze.