Data Completeness Assessment

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Data completeness is another important metric used to assess data quality. In this week's lab, we compared two sets of road networks for Jackson County, Oregon. The first dataset was from the county itself, and the second dataset was from the TIGER 2000 data. Since there is no standard methodology for measuring data completeness, we used total length of each road network as a proxy for data completeness. 

We first divided the county into a 1km by 1km grid so that each grid cell could be analyzed independently, thereby showing the distribution of data completeness across the entire county. Each road network was divided along the grid lines to facilitate the analysis of total road length within each individual grid cell. We then calculated the percent difference between the two road networks using the county dataset as the baseline. 

The map below shows the results of this analysis. The TIGER 2000 road network was more complete than the county network in 162 of 297 total grid polygons, and the county road network was more complete than the TIGER 2000 network in 134 of the grid polygons. In general, the TIGER 2000 road network is more complete than the county network. 



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