When does it make sense to combine two geocoded data sets? How can I do this?
You can combine datasets when they contain (a) different areas with records at the same geographic level (e.g., appending records for Alaska and Hawaii to records for the 48 contiguous states to get a complete dataset of all fifty U.S. states) or (b) additional data for existing records at the same geographic level (e.g., adding environmental data like average temperature for a county to the census data for a county).
