principles and working hypothesis, which are at the basis of each specific research.
It is known that a number of scientific and practical tasks solved by the mapping
method, requires a special approach to the solution of these problems. It is not likely
that one can propose universal criteria to the accuracy assessment, and, what is most
important, of scientific validity of the results obtained through maps’ analysis.
Meanwhile it is expedient to list the main factors which determine the accuracy of map
researches. Firstly, the accuracy directly depends on the goals and tasks of the research.
It is connected to the selection of cartographical sources, technical methods, volumes
of calculations and measurements, development of research methods, i.e. further
process of map analysis.
Other important factor is the accuracy of output maps or cartographic accuracy
of research. In its turn, it depends on mathematical base and scale of the map, its
modernity, validity and completeness of the content, its level of images’ generalization,
and the technology of making and publishing the maps.
The third, not less influential factor, is considered the accuracy of technical
methods of analysis or so called technical accuracy of research. It is determined by
distortions of quantitative values and accuracy of measuring instruments.
The accuracy of measurements by maps depends on the nature of the object which
is studied, and on how clearly its spatial boundaries are transmitted.
It is known that mathematical basis of topographical maps allows to reduce the
errors of planned position of the objects to 0,5-0,75 mm on a scale of a map, they are
larger in mountains and less in plain areas. The error of height position of the objects
is equal to 0,3-0,5 of the height of relief on the map. Maximum errors are twice higher
than indicated.
On small-scale maps which constitute the majority of thematic maps, the accuracy
of objects’ position largely depends on the peculiarities of cartographic projection. On
small and middle-sized territories’ maps (e.g. administrative region, physical-
geographical region, a separate state) the distortions are basically equal to 0,5-1% and
only in separate places reach 3%. On big territories’ maps (mainland, ocean,
hemisphere, whole Earth) the distortions in central parts do not exceed 2-5%, but
significantly increase to the edges.
Image generalization also impacts cartographic accuracy. As known, it effects the
degree of details provided, generalization of the content and geographical elements.
On the thematic maps errors in the objects’ position related to generalization, can equal
to 0,6-1,2 mm on the average (and sometimes 3 mm) in the scale of the image.
However, it has been proved that these errors almost don’t impact such statistical and
morphometric indicators determined by maps, as correlation coefficients, density of
objects, the ratio of areas occupied by different ranges etc. The discrepancy of the map
content to contemporary views on the depicted object may increase errors of
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