In Module 1.2 I learned about the proper guidelines involved with horizontal and vertical accuracy assessments per the NSSDA's Positional Accuracy Handbook. Using this knowledge, I was prompted to perform a horizontal accuracy test on two sets of street networks.
To perform the assessment I was given the two sets of street networks in the form of polyline shapefiles, a boundary of the study area in the form of a polygon shapefile, and a set of orthoimages covering the study area. After adding all of the data to a new map in ArcGIS Pro, I began by using the Subdivide Polygon tool with stacked block to create quadrants. I did this as 20% of my test points I was to make would need to be in each quadrant to assume 95% accuracy. Using Symbology, I next made it so the resulting polygon had no fill with an outline, thus I could still see the orthoimages while knowing where the study area boundary was. I then needed to digitize 20 points as reference points to test the street polyline files against, per the NSSDA guidelines. The orthoimages were used as a reference due to assumed dominant geographic coordinate accuracy. To create the points, I made a new feature layer with the same coordinate system as the street polyline feature layers on my map and edited 5 points in each quadrant. I used the Measure feature to ensure each point maintained a distance of 10% the diagonal length of the quadrants per the NSSDA guidelines. I created the points at intersections, marking the true center of the intersection using the orthoimages and a corresponding point on each polyline shapefile with the same point ID. I then used the Add XY Data tool to assign coordinates to each of these points. 
Pictured above is a screenshot from my map in ArcGIS Pro complete with study area quadrant boundaries (yellow), the ABQ city street data (green), the StreetMap USA street data (red), orthoimagery, and reference/test points (blue, red, & green).
Using the coordinate data created in ArcGIS Pro, I then turned to Excel to perform the horizontal accuracy assessment using the worksheet from the Positional Accuracy Handbook. Using my results I formed the following formal positional accuracy statement:
ABQ street sample tested at 17.3 feet horizontal accuracy at 95% confidence level and StreetMAP USA street sample tested at 364.9 feet horizontal accuracy at 95% confidence level.
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