GIS5935: Mod3 Data Quality - Assessment

 


In this module, we focused on assessing the quality and completeness of road network data. The main goal was to compare two datasets for Jackson County—Street Centerlines and TIGER Roads—to determine which network provides more comprehensive coverage. Completeness was measured using a simple yet effective method: calculating the total length of roads both across the county and within 1 km² grid cells. This approach allows for a spatially detailed comparison and highlights areas where one dataset may be missing roads.

The analysis involved projecting the datasets to a common coordinate system, calculating road segment lengths, and summarizing the totals for each grid cell. From this, we could determine both the overall completeness and the relative differences across the county. Numerical summaries identified which network was more complete in specific areas, while visual mapping of percentage differences highlighted spatial patterns that are not immediately obvious from raw numbers.


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