Concept analogous to that of market in economy; supply and demand for services meet and exchange in places privileged for their accessibility, which are central places. 1. In a network, it characterises the position of nodes in terms of accessibility (see centrality index), the centre being the place endowed with maximal accessibility; 2. For a […]
Model elaborated by the German geographer Walter Christaller in 1933, derived from the central places theory which gives account of the size, spacing and number of cities. The model describes the hierarchical organisation of a network of cities according to the level of services they provide, and their regular spatial disposition on the vertices of […]
A city system; is a group of cities, which, in their evolution, have become interdependent because of the many relationship networks that they have and that interconnect them to a greater extent than other cities located in the environment. It is often the borders of a national territory that constitute the boundaries of a city […]
Term of psychology, relative to knowledge processes (acquisition, storage, use and processing of information), used in geography of perception, or of representations, or of experienced space; relative to an individual or collective representation of space, in function of a knowledge or of a practice. The cognitive map (or mental map) designates either this mental representation, […]
In theory of graphs, intensity of interlinking between nodes through edges of a network; more generally, degree of internal connection of a network. As opposed to mere proximity relations, called relations in continuity, connectivity relations are those using the support of a network to link two places that may be far apart from each other.
(from Latin contingere “to touch”) Two geographical units are contiguous if they have a common border. A contiguity matrix is a square table whose cells indicate (generally by means of one or zero) whether the geographical units mentioned in row and in column are contiguous or not. A contiguity constraint may be added to a […]
Interval to cover in order to go from one place to another, distance has a meaning of separation, its covering requires effort, expense of energy. The mathematical definition of distance is restrictive: a measure of gap between objects is a distance if it is symmetrical, if it is not negative, if it is null only […]
(from Greek dynamis “force”) Process of change, or evolution, resulting from action of forces: the dynamics of unequal exchange produces a centre-periphery structure. Dynamic models link changes with the forces that generate them, whereas kinetic models describe changes without reference to forces. In human geography, the term dynamics implies a notion of change, and not […]
Spatial analysis refers to one of the main uses of the term « space », common to geographers, to specialists of spatial economy or of regional science. Space is here a relative space, produced, defined by relations between places that develop because of interactions between localised social actors. This concept is distinct from the more […]
In physics, equilibrium is the state of a system subjected to opposite forces that balance each other, so that the variables describing the system stop evolving and any move is stopped. In geography, what may rather be observed are stationary states, when equality of incoming and outgoing flows of an open system implies that there […]