Thousands of data at a glance: Shaded contour maps of demographic surfaces

Contour maps are useful for displaying demographic surfaces, including surfaces of population levels and fertility, marriage and fertility rates. Most often the surfaces are defined over age and time, but other dimensions can be used such as life expectancy or population growth rate. This research report presents a bouquet of contour maps to suggest the broad potential of their use in demographic studies. The maps presented range from maps of Italian mortality, French population levels, and U.S. birth rates, to maps of Coale and Demeny’s and Brass’s model life tables. The value of the maps lies in their substantive import: by giving demographers visual access to population surfaces, the maps can help demographers uncover and understand population patterns. The text of the research report adumbrates some of these patterns and discusses the use of contour maps in exploratory data analysis and model building, including the use of maps of residuals in fitting models to data.