Which data layer must be considered to determine if a ZIP code is covered by a CSA in SAD?

Which data layer must be considered to determine if a ZIP code is covered by a CSA in SAD?

• A. The ZIP code layer
• B. The CSA layer
• C. The route layer
• D. The payroll layer

Answer: (B)

To determine if a ZIP code is covered by a CSA, you rely on the CSA layer because it defines the geographic boundaries of CSAs. The ZIP code layer only tells you where ZIP codes are located, but it doesn’t indicate which CSA covers them. By performing a spatial check between the ZIP code polygons and the CSA polygons—seeing if they intersect or if a ZIP code’s area or centroid falls inside a CSA—you establish coverage. The route layer and payroll layer aren’t about CSA geographic coverage; they serve different purposes like routing or payroll data. Remember, ZIP codes can cross CSA boundaries, so you’ll apply your chosen rule for assigning coverage (e.g., containment, centroid, or majority area) accordingly.

To determine if a ZIP code is covered by a CSA, you rely on the CSA layer because it defines the geographic boundaries of CSAs. The ZIP code layer only tells you where ZIP codes are located, but it doesn’t indicate which CSA covers them. By performing a spatial check between the ZIP code polygons and the CSA polygons—seeing if they intersect or if a ZIP code’s area or centroid falls inside a CSA—you establish coverage. The route layer and payroll layer aren’t about CSA geographic coverage; they serve different purposes like routing or payroll data. Remember, ZIP codes can cross CSA boundaries, so you’ll apply your chosen rule for assigning coverage (e.g., containment, centroid, or majority area) accordingly.