Choropleth Map Accuracy: Characteristics of the Data
نویسنده
چکیده
The accuracy of maps based on aggregate data is dependent upon (a) the extent to which aggregate values calculated for each enumeration unit are representative of the entire unit and, (b) the data classification system used to assign these values to classes. Size and compactness of these units as well as the variability of the distribution mapped are important factors in determining the accuracy of aggregate values calculated for the units. In this study, the individual and relative importance of these enumeration unit and surface characteristics are examined. Analysis indicates that all three variables exert a significant influence on accuracy of aggregate values with surface variation accounting for the greatest portion of the varia tion in accuracy.
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