Looking for a Tool to Calculate Distance Between Points (Between Layers)
I am a college student using ArcEditor 10.0 for a semester project measuring distance to hospitals from census tract centroids. This is my first time using ArcGIS, and I have no formal training. So this question may be very simple, but is it possible to calculate distance between two different types of points between two layers? In one layer I have a shapefile for census tracts and I've calculated the centroids. In the other layer I have geocoded hospital addresses. I would like to calculate distance from each census tract centroid to the nearest hospital. Is there a tool in Arc Toolbox that will do this/could you give a brief overview of the tool?
Since you have ArcInfo, you can use the Near geoprocessing tool to find the distance. It's in ArcToolbox > Analysis > Proximity. Your input features will be Census tract centroids and your near features will be hospitals.
You may want to consider running the analysis simply on the Census tract polygons instead of their centroids. Tracts are large and often very odd-shaped, especially in rural areas. If you use centroids, you can end up with weird-looking results if elongated panhandles are close to a hospital but that tract's centroid is still far.
Moreover, you may also want to consider using a higher spatial resolution Census geography, e.g. block groups or blocks. American Community Survey data are available down to the block group resolution, and would probably produce better looking results.
Perform a spatial join. Make sure the two layers are first projected appropriately, because the distance will be computed using the Pythagorean Theorem (not using spherical geometry). To access it, right-click on the target layer name in the TOC, choose "Joins and Relates," and fill out the dialog like this (where "CITIES" is the source layers), paying attention to option 2:
A new dataset will be created and added to the TOC. It has one record for each of the original records in the target layer. The last field in its attribute table contains the computed distance to the nearest source feature.
(This capability, which is part of the base ArcView functionality and therefore needs no special licensing (unlike
Near) has been part of ArcView since version 2; only the interface and output format have changed.)