Thursday, February 13, 2025

Module 5 - Geocoding Manatee County Schools, Florida

 

This week’s lab project was an introduction to geocoding tools in ArcGIS Pro. We learned how to geocode a list of schools addresses from an excel sheet to create a point layer showing the schools location in a map.

I started with copying and pasting the schools list data from Florida Department of Education to a new excel sheet. I then cleaned the data, so that only the school’s name, type, address, city, and zip code fields populated and saved the excel sheet as .csv file. I downloaded Manatee County Street layer and boundary shapefiles from US Census Bureau geographic program TIGER/Line Shapefiles. Subsequently, I created a new ArcGIS Project “Geocoding” and added the two shapefiles; Manatee County streets centerlines and boundary shapefiles. I also added the new school list .csv which I created earlier.

The next step was to create an address locator from the streets centerline layer using Create Locator tool and named it ManateeAddressLocator as the output name. At this stage, I was ready to geocode the schools list against the new created address locator. Running geocode table from the geoprocessing pane, the result was 6 records not been geocoded out of the 84 records I had. Thus, I must manually geocode these records. To do that, I used the Rematch Addresses tool to manually geocoded these records, using various sources such as locating the address in ArcGIS Pro or using Google map search.

Three records out of six required additional investigation. Two of these records contained P.O. Box numbers in the address field. I successfully identified one school by searching Google Maps for the school's name, while the other remained untraceable. The third record had an address situated in a different county, which led me to exclude it from the layer.

Upon reviewing the result layer, I observed that nearly all points were positioned along the road centerline rather than on the actual buildings or parcels, with a few located incorrectly. To rectify this, I adjusted the points to their appropriate locations.

To further validate my findings, I downloaded two additional layers: the parcels layer and the address points layer from Manatee County's open data website. Subsequently, I created two new address locators, one based on the parcels layer and the another on the address points layer. I was uncertain about the effectiveness of this approach; nonetheless, I proceeded forward. I then executed a new geocoding process on the .csv file, first utilizing the parcels layer address locator and then the address points locator. Both methods yielded identical results and locations for the school points. Out of curiosity, I also conducted a new geocoding using ArcGIS World Geocoding Service and the results were comparable to those obtained with the parcels and address points locators.

In summary, it is my belief that utilizing the parcels or the address points layer to create an address locator yielded greater accuracy in locating schools compared to the street center line method. Furthermore, employing ArcGIS World Geocoding Service proved to be the most effective option, although it does require the consumption of ArcGIS credits. Moreover, data quality remains a critical concern in the realm of geocoding, as inaccurate or incomplete addresses can result in significant and time-consuming difficulties. The concluding task involved the development of a web map application that displays the locations of schools in Manatee County.

Web map app link: 


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