central place

8/2/2019 Central Place

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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

central place

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