Spatial Data Standards

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In this lab, we were asked to compare the horizontal accuracy of two street datasets for the city of Albuquerque, NM. One of the datasets came from the city itself, and the other came from StreetMap USA. Below is a general outline of the process followed.  

  1. Selected 20 test points for both datasets evenly distributed throughout the study area. These test points were located at clearly defined intersections. 

  2. Created a reference for each test point based on orthomosaic images.

  3. Generated XY coordinate data for test points and reference points and calculated accuracy statistics using the following table. 


    Figure from the Positional Accuracy Handbook. 1999. Minnesota Planning, Land
    Management Information Center, St. Paul, MN


The map below shows the location of the 20 test points selected. 



Results


City of Albuquerque Dataset

Tested 13.206 feet horizontal accuracy at 95% confidence interval. 


StreetMap USA Dataset

Tested 241.367 feet horizontal accuracy at 95% confidence interval. 






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