concentration of objects: density, uniformity of networks; complexity, grinding,
homogeneity and heterogeneity of contours.
Mathematic-cartographic modelling lies, from one side, in constructing
mathematic models of objects of the real world by map data, from the other side, in
constructing new maps by these models. Transformation of mathematic model into
cartographic one makes the research results visible both by stages and in the whole,
allows to check the precision of mathematic transformations and geographic
correctness of the obtained result. So, we have the chain: map → mathematic model →
new map.
The principle opportunity of using mathematic methods in the maps’ analysis is
based on determination of objects’ position on the map by the function z = f ( x, y), i.e.
each point on the map with coordinates x and y has only one value z of the depicted
object. Connections between several objects can be expressed both by functional and
statistical dependences, be functions of not only space, but of time as well. Mathematic
transformations allow to get rid of insignificant details in objects’ characteristics, to
replace complicated and unknown dependencies by simpler and more known ones.
Most developed and successfully used in geographic researches are methods of
approximation theory, mathematic statistics and some branches of information theory.
Exploration of cartographic image can bring effective results only in case of
studying not separate objects but its multitude, e.g. images of all rivers or all
settlements at any big enough part of the map. Such study is called statistical. It is one
of ways of knowing objective laws of reality. In the process of statistical study of
phenomena statistical regularities are revealed, which are true for the whole mass of
objects and phenomena in total. In a separately taken phenomenon they may not be
revealed. Statistical researches reveal in so called chaos of subjects and allow to
confirm the presence of causal connections in the studied phenomenon. Mathematical
statistics techniques are used to solve with the help of maps the following main tasks:
determination of generalizing statistical indicators of the objects depicted at the map;
study of the form and density of connections between objects depicted at different
maps; assessment of the level of separate factors’ impact on the object under study;
selection of main factors.
Indicators of mathematical statistics are: partiality (size which is most often met
at this part of the map), median (size which shares the orderly selection in half),
average arithmetic (is a fraction of the division of the sum of all variants into their
number), weighted average arithmetic (is calculated taking into account the relative
weight of each variant or each interval within the sample), swing (amplitude of a
number of variants obtained from the area of map which is analyzed), or the amplitude
of values, coefficients of variation (is defined as the percentage of ratio of the mean
square deviation to the average arithmetic), correlations etc. To characterize the
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