1. Data Quality for GIS
2. GIS quality-related issues
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3. Data Quality
4. GIS Projects – Cost versus Accuracy: Hypothetical Exam...
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5. Request to develop land use layer for Texas town
6. Data Quality Concepts
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7. Accuracy, precision, resolution
8. Types of accuracy requirements
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9. Types of error
10. Positional error
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11. Source of the “true value” for estimating accura...
12. US National Map Accuracy Standards (Paper Maps)
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13. “Source scale” is one determinant of positional ...
14. About Scale
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15. Large and Small Scale Maps
16. Scale 1:100,000 (1 inch approx 1.58 miles)
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17. Scale 1:24,000
18. Scale 1:10,000
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19. Scale 1:2,000
20. Relation between positional error and scale
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21. NMAS Standards
22. Digitizing paper maps adds error
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23. Attribute accuracy
24. Logical Consistency
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25. Completeness Is the data set “complete”?
26. Currency: Is the data set current? No!
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27. Ensuring data quality
28. Ensuring data quality
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29. Ensuring data quality
30. Documenting data quality
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31. What positional accuracy do you need?
32. What attribute accuracy do you need?
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33. GIS quality-related issues
34. Metadata is critical!
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35. Web sites with more information
36. Learn more about metadata
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