GIS4930 - Module 1.3 - Assessment

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For this module, we were tasked with comparing the completeness of two road datasets for Jackson County Street Centerlines and TIGER Roads. We used a 1 km x 1 km grid and analyzed which dataset had more total road coverage both across the entire county and within each individual grid cells.

We started with both datasets and projected the, into the same coordinate system and clipped to the county boundary to focus only on relevant roads. Each road network was intersected with the grid so that road segments were split wherever they crossed a cell boundary, then a new field was added to calculate the length of each segment in kilometers.

I used the Spatial Join tool to sum the total road lengths for each grid cell for both datasets. These totals were combined into one table and a percentage difference was calculated to determine which dataset was more complete within each cell. I used the Select By Attributes tool was then used to count the number of cells.

This resulted in Street_Centerlines being more complete in 66 Cells TIGER_Roads is more complete in 229 Cells.

 

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