TERRITORIAL OR GEOGRAPHICAL SERIES

The territorial or geographical series are used to present the geographical distribution of events. Such a presentation is possible only on a map of territorial division. Facts relating to each territorial unit or the sum of values corresponding to these facts are given; sometimes the intensity of a given phenomenon in each territory may be given instead. It may be the number of farms or the total area of arable land in each county, the number of traffic accidents in different precincts of a city, or the population density in different parts of a country. Each phenomenon may require its own type of territorial unit, the one that is most natural from its point of view. Each unit should be as uniform internally as possible, and the contrasts between one and another should appear between particular units. Cartogram is a map on which the geographical distribution of statistical phenomena is marked. As a base, a schematic map is commonly used. All the details that might obscure the statistical picture are usually removed. Very often only the administrative boundaries are marked.