Horizontal Accuracy

This week, I tested the horizontal accuracy of two street datasets in Albuquerque, NM.  I tested the City of Albuquerque dataset and the StreetMap USA dataset. To complete this analysis, I overlaid the two street datasets on orthophotos of Albuquerque. I used the orthophotos to identify the true location of 20 intersections.  After establishing these reference points, I identified the location of those intersections within the Albuquerque streets dataset and the StreetMap dataset, added XY data for all points, and used the NSSDA datasheet to compute the accuracy of each dataset.  Please see the map below for the location of intersections used in the analysis.

The Albuquerque dataset proved to be much more accurate than the StreetMap dataset and the accuracy statements for each are listed below:

ABQ Streets

Positional Accuracy: Tested 13.15 feet horizontal accuracy at 95% confidence interval.

 

StreetMap Streets

Positional Accuracy: Tested 353.50 feet horizontal accuracy at 95% confidence interval.

The relative accuracy of these two datasets is not even close, and it is clear which dataset would best be used for navigating the streets of Albuquerque.