The first assignment of Special Topics in GIS was on making a buffer graph detailing the distance percentages from a averaged waypoint. In this assignment we were able to take an average of the cluster of points above and then establish a baseline around it ranging from a percentile mark. It is also detailed in a meter format with each ring spreading out so far (detailed in the legend). We also had to detail the horizontal accuracy and precision in here as well. The horizontal accuracy for this was 3.24 meters and the horizontal precision was 4.5 meters. Which definitely had a bit of a difference between the two of over a meter. The horizontal accuracy is determined by having our average waypoint (detailed in the map above by the yellow star) and a reference point (determined through GPS marking which isn't listed on the map because it came in a later part of the assignment). The accuracy is determined by using a tool in ArcPro called measure which lets you click on both points and it tells you the difference between the two points. The horizontal precision is defined by the 68% percentile of the waypoints data. This is where most of the data tends to fall into so it is used as the standard for the precision. So in this is 4.5 meters (precision) minus the 3.24 (accuracy) which is 1.26 meters. Which isn't terribly far off for doing GPS work but there is definitely a difference between averaging points and having a defined GPS point from the field.
This week was a very informative and useful assignment for detailing GPS efficiency and accuracy!
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