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THE URBAN SYSTEM
CENTRAL PLACE THEORY and
RELATED CONCEPTS
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The US at night
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Is there an order to this?
Maybe itsan
underlyinggeometry inthesettlementpattern
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Is there an order to this?Maybe allwe need to
do isrearrangethe citiesslightly tomake thepattern
apparent.
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OBJECTIVE to understand the dynamics shaping
the urban hierarchy what makes cities grow quickly or slowly? how do urban settlements of a particular
size affect the emergence and growth ofother settlements of the same or different
size? what pattern would the system of
settlements form in the absence ofcomplicating factors such as topography
and history?
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Why ask these questions? to advance toward a more scientific
understanding of urbanization
to develop a foundation on which to build apositivist theory of urban growth to raise urban studies to the level of the
hard sciences--assuming the hard sciencesare superior to the soft (humanistic,descriptive, probabilistic) sciences
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Every science needs a force economic competition
between cities
rational maximization by individuals
friction of distance as a driving force cost distance time distance (later) cognitive distance
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In short Through rationally maximizing the
productivity of their time
by minimizing the costs of various activitiesmeasured in money and time,
people collectively create a system in whichfacilities of all sorts
including cities, are pitted against each other and all facilities emerge from this competition
in advantageous locations and with
predictable-sized areas of dominance.
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Competition Produces Order
In other words
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Founders of Central Place
Theory C.J. Galpin (1915)
sociologist studying rural communities in Wisconsin decided that under ideal conditions settlements
would be spaced evenly pattern: overlapping circular service areas with the
central places aligned in a hexagonal array overlap of service areas indicates a region in which
a person is equally inclined to shop at either centralplace
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Galpins model
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Founders of Central Place
Theory Walter Christal ler (1966)
assumption: each good has itsparticular range and threshold
threshold of a good: minimum sizeof market capable of sustaining abusiness devoted to that good
range of a good: maximumdistance a person will be willing totravel to obtain that good
associated assumptions variations in range and threshold
from person to person or fromculture group to culture group areirrelevant
most people will shop at only onecenter
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Details of Christallers theory The vast range of retail functions could be
grouped into 7 orders, corresponding tocities with different sized hinterlands
the functions in an order share a similarthreshold and range automobiles would be in a different order
than loaves of bread, for example What might be in the same order as
automobiles? What might be in the same order as loaves of
bread?
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Hypothetical pattern of central
places
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More terminology Higher ordergoods and services are those
with a wider range and higher threshold,located in larger urban centers
Lower ordergoods and services are thosewith a narrower range and lower threshold,located in smaller urban centers
break point: the invisible boundary betweenmarkets of competing central places isotropic plainuniform land surface on
which these ordering principles would
generate a hexagonal pattern of cities
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An interpretation of the urbanhierarchy (listed by order)
1. largest cities (all functions, highest to
lowest)2. large cities
3. small cities
4. larger towns
5. smaller towns
6. villages
7. hamlets (only the lowest order functions)
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Variations on the basic theory
different patterns result from different valuesof k
market optimizing, k=3 (minimizes totalnumber of settlements serving a region) traffic optimizing, k=4 (emerges by
minimizing the road lengths joining all
adjacent centers) administration optimizing, k=7 (assumes
lower-order places must be contained in theadministrative districts of higher order places;
can not be situated on the breakpoint)
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Market principle (a) andtransportation principle (b)
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Market principle
Transport principle
Administrativeprinciple
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The US at night
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Cool idea, not much basis inreality
cities just dont form these patterns they do respond to some kind of
hierarchy-forming process,however
evidence:
the rank-size distribution alternative explanation:
connection rather than competition: thepower function law of networks
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settlement order
& predicted frequenc
1
10
100
1000
10000
100000
1000000
02468
order
marketing principle
transport principle
administrative principl
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Founders of Central PlaceTheory
August Lsch (1954) similar to Christallers theory but without
the classification of urban functions into afinite number of orders
implication was that cities could be any sizeand would form a continuous distribution of
sizes
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Power laws and scale-freenetworks
Recent research on networks of various types (Internet, neuralnetworks, social networks, electrical grid, ecological systems,biochemicals, brains) has revealed that the hierarchy of nodedegree consistently follows a power law relationship: straightline on a log-log graph.
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What would this indicate?
Urban hierarchys regularity may not becaused by the random perturbation of
what would ideally be a step-wisefunction caused by competitionbetween cities
Instead, it may be caused by thenatural emergence of dominant (hub)nodes within a dynamic network