Week 11: Geocoding and Network Analyst

The objective of this lab was to geocode by address matching and complete a route analysis for EMS station locations in Lake County, FL. For the lab, I downloaded a 2017 US Census Bureau Tiger Line shapefile for Lake County, FL from their web interface. This data was projected to NAD 1983 Harn State Plane Florida East FIPS 0901 Feet using the Project tool. I then created an address locator using the Create Address Locator tool from the Geocoding toolbox. Using this address locator, I mapped or geocoded known EMA station locations from address and zip code. Thirteen of the addresses were matched but there were still 8 unmatched results. Two of the unmatched addresses had possible matches. In order to match the address, I added the street maps basemap and zoomed to the layer to check the matches against the street names and addresses. In order to match the remaining locations, I looked up the addresses in Google maps, found the largest nearby street, used Select by Attributes to locate that street and then zoomed into and selected the location on the road closest to the point for the match. Some of the reasons for the errors in the unmatched addresses were misspellings in the data, missing direction identifiers in the street name and street type and abbreviations missing, misidentified or misspelled. Finally, I used the Network Analyst extension to create an optimal route between 3 of the EMS stations. I found it easy to add stops to the route by selecting each desired location which were then snapped to the street network. The parameters for the optimal route analysis were: impedance in minutes; distance cost in miles; oneway, turnrestrictions, and unbuiltroadrestriction restrictions; all uturns; and arrive/depart time as Today at 8:00AM. The final map shows the optimal route created with these settings.

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