result. For spatial analysis the important information is that representing geographical
object as it looks like, and also information about the structure, spatial integrity, the
nature of variability of objects. Our world consists of many geographical objects which
are expedient to be decomposed to the types for performing analysis. The type of
geographical objects determines the essence of analysis process, selection of methods
and analysis order.
Discrete geographical objects – are separate microbodies, phenomena of real
earth’s space.
Each discrete object is separated from other objects in space or time and always
occupies specifically determined place in space.
Continuous phenomena (fields) characterize the territory as a whole, not separate
objects. Continuous phenomena are phenomena that constantly change in space and do
not have gaps. Continuous data are represented as:
- continuous surfaces, emphasizing changes of quantitative index with change of
the place;
- regular or irregular sets of points (GIS evaluates the presence of this type data
by density of observations);
-
Restricted areas which contain the same type data (the boundary of the area
indicates the discrete change of index in the area).
Objects aggregated by area, reflect the generalized characteristics or
concentration of separate objects within the area. Objects aggregated by area,
characterize the total number of other objects within the area or their aggregated
indicators. The value of the indicator characterizes the area as whole, not each point
separately. Statistical indicators are aggregated for certain territory. Aggregate
indicators are characteristic for administrative districts, post offices etc. The data can
be created by:
- statistical analysis – by code which determines affiliation to any area;
- overlay analysis – graphically allocated objects which are located within these
areas.
Both discrete and continuous events can be aggregated. By structure geographical
objects are divided into elementary (simple), composite and complex.
An elementary object does not have constituent parts (e.g., a separate building).
A composite object is formed by a group of other objects in a certain (directed)
order of its formation, which is determined (e.g., a separate building consisting of
parts).
A complex object is formed by a group of other objects (elementary, composite,
complex), the order of passing in formation of the object is determined as non-fixed
(e.g. a group of buildings).
By the form of existence geographical objects are divided into material (real) and
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