A duplicate is a copy of an existing data set which can be used for comparison purposes. It allows users to make an exact replica of another set without having to change any of the original values. This makes it easier to check the accuracy of one dataset against another as well as provide a snapshot look at how two datasets may differ from each other.
Overlap refers to when two sets share some common elements but also have distinct differences between them. For example, if there are overlapping circles on a map representing different population densities then this would represent an overlap because although both circles contain certain elements (i.e., area covered by the circle) they also have unique qualities that differentiate them (i.e., different population levels).
Compare a contrast a duplicate, overlap, and overlay.
Finally, an overlay is when two datasets are placed on top of each other so that they can be compared more visually and efficiently than with either duplicating or overlapping processes alone . This method allows users to quickly identify similarities and differences between two sets more quickly than if done manually since all relevant data points will be included in same place making easier spot patterns discrepancies .
In conclusion , while all three methods provide useful means comparing datasets variety ways , duplicates offer exact replica source allowing check accuracy easily yet require alteration original Overlaps able identify similarities distinct differences presence common elements whereas overlays allow quick detection trends anomalies due visualization aspect . < br >References: < br > Longley P., Goodchild M., Maguire D., Rhind D (2015) ‘ Geographic Information Systems An Introduction’ John Wiley & Sons