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About These Maps

The Appalachian Regional Commission generates county-level maps to graphically display potential geographic patterns and spatial correlations in the data of various socioeconomic topics. These visual representations of the data reveal hidden patterns and conditions that may lead to further analysis, research, and regional policy development.

Some of the data topics include two maps, one representing absolute data and one representing relative data. Absolute data are computed values derived from the source data and allow for comparisons between counties. Relative data are comparisons of absolute data with national averages; they are expressed as percentages in order to compare each county's performance with the U.S. as a whole.

The maps employ a technique that classifies the data into generalized groups of common values and assigns a color to each group. To allow for the comparison of geographic patterns between maps, darker colors are consistently used to represent counties with problematic socioeconomic indicators, such as low income values, high unemployment rates, and high poverty rates. The maps of absolute data use a classification scheme that organizes the data into groups based on relatively large jumps, or "natural breaks," in the data distribution. The maps of relative data use a "critical breaks" classification scheme, which groups data based on national averages and other critical thresholds.