Special Topics Week 1: Data Quality

For this lab, we explored different ways of assessing the quality of spatial data, including precision, accuracy, root mean square error (RMSE), and a cumulative distribution function (CDF). I created the map below to show the horizontal precision and accuracy of a dataset of 50 points recorded at the same location by a Garmin GPSMAP 76.

Horizontal accuracy is the distance between the true value (the yellow point) and the mean of the recorded values (the red point). The horizontal accuracy is 3.2 m. Horizontal precision is how close a set of recorded results are to each other. A common metric for precision is the 68th percentile: the value that is greater than or equal to 68% of the observations. For this data, the horizontal precision is 6.7 m. On the map, the second buffer has a radius of 6.7 m, and includes 68% of the Garmin measurements.

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