Imagine that I have 40 observations in region A, and 50 observations in region B. The total size of region A in square kilometers is 50km, and the total size of region B is 40km. Within each region, each observation has a count of events that ranges from 0 (fairly frequent) to 20.
What is the best way to hypothesis test for a difference in mean events per square kilometer between region A and region B?
I've considered the following options: 1) Using a negative binomial regression with the area of each observation as a covariate. 2) Scaling the dependent variable (event counts) somehow. 3) Subsetting A and B via matching to achieve an equivalent total area on each side.
Thanks in advance.