objectives differentiate accuracy, precision, error, and uncertainty. discuss the dimensions of...
Post on 21-Dec-2015
219 Views
Preview:
TRANSCRIPT
Objectives
• Differentiate accuracy, precision, error, and uncertainty.
• Discuss the dimensions of geographic data quality.
• Discuss how to compute RMSE for positional accuracy.
• Describe why data standards are beneficial
• Key terms: metadata
•Accuracy—how close to “true”
•Precision—how exactly measured and stored
•Error—deviation from “true” value
•Uncertainty—lack of confidence due to incomplete knowledge
Inherent = Source
Operational = user
or processing
Semantic DiscrepanciesSemantic Discrepancies
• RMSE = sqrt(average(squared discrepancies))
• x, y, and z (or e)
• p = sqrt(x²+ y²) (Positional)
• Use p and e for map overall
Metadata—Geographic Data Quality
• Lineage
• Positional accuracy
• Attribute accuracy
• Logical consistency
• Completeness
Spatial autocorrelation
Sampling
Standards vs Translators
top related