Urban Service Centres
• Cities as centres of...
• Control
• Production
• Distribution over a homogenous
umland
• uniform distribution pattern
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Central Place Theory:
Explaining the Geography of
Urban Service Centres
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Model: noun, verb, adjective
Spatial model
Abstraction
Simplifying assumptions
Theoretical basis for urban (Central
Place) hierarchies
• Walter Christaller The Location of
Central Places in Southern Germany
(1933)
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Simplifying assumptions:
• Land Area
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isotropic surface (flat / homogeneous)
unbounded plain
no variation in raw material distribution
equal ease of movement in all directions
transportation costs proportional to distance
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Simplifying assumptions:
• Population
• Homogeneously distributed
• Homogeneous demand
• Tastes/preferences
• Spending
• Behaviour
• Rational Economic Persons
• aware of alternatives
• producers=profit-maximizers
• consumers=optimizing
• perfectly competitive market
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Market and Demand
• Market is a point location
• Distributes its goods within a
market area.
• Demand for good:
• Market price (fob market)
•+
• Cost of transport (to & from) market
Demand
Distance
Real Price per Unit
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Q Demanded
Market location
FLIP
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Q Demanded
FLIP
Q Demanded
Spatial Demand Cone
Demand
Distance
Distance
Market location
Increasing
real price
RANGE:
The spatial extent of
demand before
demand drops to zero
Distance
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Distance
Demand = zero
Threshold
Market
Threshold
Range
Range
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Important definitions:
• Threshold:
• minimum DEMAND (volume of sales) needed
for a business to stay in operation
(and make a “normal” profit).
• Range:
• maximum distance over which a good can be
sold from point P
(i.e. where real price is low enough that people
will travel to market to buy it)
• Profit = R - T
• Threshold and range is the spatial basis
for profit
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Implications of the RANGE
Area of Extra Profit
Min area required to stay
in business (normal profits)
Isotropic surface
R
M
T
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Unmet demand for
same good or
service