Vector Data

  • Polygon misclosures;
  • Overshoots/undershoots;
  • Polygon labels;
  • Knots, backtracks, wild lines
  • Slivers and gaps
  • Map sheet combination
  • Line generalization


Raster Data

  • Noise removal: uncharacteristic pixel values due to malfunctioning of system used to collect data or some items that were in the dataset if not required. Removed by digital
  • Line thinning: making lines to be one pixel wide
  • Gap removal: no pixel values due to malfunctioning of system-average corresponding scan lines
  • Stray pixel removal: clearing pixel falling in wrong locations
  • Re-assigning: giving pixels different values, happens when resampling size of the image

Attributes Data Errors

The identification of attribute data errors is usually not as simple as spatial errors. This is especially true if these errors are attributed to the quality or reliability of the data. Errors as such usually do not surface until later on in the GIS processing. Solutions to these type of problems are much more complex and often do not exist entirely. It is much more difficult to spot errors in attribute data when the values are syntactically good, but incorrect.

Simple errors of linkage, e.g. missing or duplicate records, become evident during the linking operation between spatial and attribute data. Again, most GIS software contains functions that check for and clearly identify problems of linkage during attempted operations. This is also an area of consideration when evaluating GIS software.