Module 1.1 Lab: Calculating Metrics for Spatial Data Quality

 In this week's module, we learned about precision vs. accuracy and how to determine both. The data used were waypoints collected by  GPS units. An average way point was determined to calculate the precision while a reference point was used to calculate the accuracy. 

After the average waypoint was calculated, the 68th percentile was estimated for the 50 values to be 34. Adding the values of the 34th and 35th index and then dividing it by 2 resulted in a horizontal precision of 4.3 meters. 

For accuracy, a reference point was used that is the true point of the waypoint location. Instead of making any calculations, the measure tool was used resulting in a distance of 3.49 meters. 

Horizontal precision provided a larger distance from the waypoint meaning lower accuracy. The horizontal accuracy is better because the distance is shorter and the measurement is based on a true point vs. the precision's average point. 

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