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Conflicting polygon data (overlapping)

November 22 2010 | 0 comments
Categories: Symbology

Hi I have a request to make a map showing areas within 20min from a facility. They want to see pop density and industrial land on the map as well. Pop density is a raster and industrial land is a polygon feature class. The data overlaps each layer. Do you have any suggestions on how to display all this information elegantly on a map? I'm currently using transparency to see the layers underneath.

Mapping Center Answer:

Your options are limited when you have two polygon distributions. The fortunate thing is that you have one quantitative distribution ( population density) and one qualitative one (industrial lands). As you can imagine, the population density would best be shown with a sequential color scheme (one color such as red, green or blue, from light to dark with the darker colors representing the higher values). Then the quantitative distribution (industrial lands) could be symbolized using another method that does not conflict with this. Perhaps the best solution is to use a different OUTLINE symbol for these lands. Other solutions might include the use of a hatching fill symbol or labels but either of these will cause the areas to look darker than they really are, because of the additional color shown in the areas for the text or the line hatches.

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