Models for AP Exam
Three Key Models for
Urban Land Use
Burgess – Concentric Zone
Hoyt – Sector Model
Harris and Ullman – Multiple Nuclei
Some General Notes on
Central Business District
• Definition: CBD- original core of a city’s economy,
like a nucleus of a cell
• CBD is compact, less than 1% of urban land area
• Contains a large % of shops, offices, and public
institutions
• Consumer services and business services are attracted
to the CBD because of its accessibility
• Center is easiest part of city to reach from the rest of
the region
• Focal point of region’s transportation network
General Notes on
Central Business District (Cont)
• Characteristics of a CBD
• High land costs
• Discourages Industry in the CBD
• Intensive land use --Skyscrapers
• All of the following models possess a central
business district
• Degree of influence and geographic location of CBD
varies throughout different models
Three key theories for Urban Land Use
• Burgess – Concentric Zone
• Hoyt – Sector Model
• Harris and Ullman – Multiple Nuclei
Concentric Zone Theory
• Burgess (1925)
• 1st model to explain and predict urban growth
• All other urban models are built on this model
• Model suggests that a city’s land use can be
viewed from above as a series of concentric rings
• Cities grow outward from the centre in a series of
rings
• As the city grows and expands, new rings are
added and older rings change their function
• Size and shape of rings vary per city
Burgess Concentric Zone Theory
• Timeframe
• 1920’s
• Class conscious
society
• Housing segregated
according to income
• Lack of transport
infrastructure
• Assumptions
• Older buildings in city centre
• Newer buildings at edge of
city
• Land values highest in city
centre
• Strong economic and ethnic
segregation
• Low income groups lack
transport and live close to
city centre
• Cities develop on a flat plain
with equal access to
transport
Place this in your memory bank
The Five Zones - Burgess Model
• 1) Central Business
District-non residential
activities
• 2) Transition and
Industry
• Low incomes
• Oldest housing
• Ghettos
• Immigrants often
live here
• 3) Low Income Residential
• Stable working class
• Modest older homes
• 4) Middle Income Residential
• suburban estates- good
quality homes - gardens
• 5) High Income Residential/
Commuter
• Small towns and villages
Burgess Concentric Zone Theory
• Model assumes a process sometimes called
invasion and succession (or succession migration)
• Definition:
• New arrivals to cities first tend to move to the inner
rings near the CBD
• This pushes the people and economic activities
already present out into further rings
• This constant pattern can lead to a ring known as
the zone in transition
• Zone outside CBD--never really developed
• Developers know that it will be constantly caught in
shift
• Sometimes called “skid-row”
What are some of the problems with
the Burgess model?
• Old
• Doesn't consider car ownership
• Landscape not considered
• Impact that industry and transport could have
on land use not considered
• Zones are never as clear-cut
Homer Hoyt (1895-1984
• Land economist, a real estate
appraiser, and a real estate
consultant
• Conducted path-breaking research
on land economics
• Major figure in the development of
suburban shopping centers in the
decades after World War II
• His sector model of land use
remains one of his most well-known
contributions to urban scholarship
1939-Sectors radiating out from the
CBD along transport routes
Hoyt’s Sector Theory
• Timeframe
• Late 1930’s
• Income and status
divided society
• Housing areas reflect
social segregation
• Assumptions
• Settlement develops along
transport routes
• Towns radiate out from
the CBD
• Low-income and industrial
areas lie next to each other
• Wealthy people choose
the best sites
Criticisms of Hoyt’s Theory
• Old
• Too general
• In reality, most zones contain more than one land-use
• Doesn't consider the impact of urban renewal
schemes
Burgess ‘v’ Hoyt
• Hoyt’s theory is based on statistical
data, so it’s less open to the
criticism that Burgess received
Harris and Ullman’s Multiple Nuclei Theory
• 1945
• Premise: as an urban area grows, it
develops around a number of different
business centers or nuclei.
Multiple Nuclei Theory
• Assumptions
• Modern cities more
complex than suggested
by other theorists
• Each nucleus acts as a
growth point
• Growth occurs outward
from each nucleus, until
they all merge into one
large urban area
Multiple Nuclei Theory
• Mixture of Burgess and Hoyt
• Shows some land-uses attract
more of the same, for example
industrial areas
• Some land-uses may deter
others from locating nearby,
e.g.; housing is usually located
away from industrial areas
Criticisms of Multiple Nuclei Theory
• Not an exact fit for
all cities and towns
• Too complex
Are these models relevant to today’s cities?
• They have some relevance
• Now due to urban renewal schemes
and changes in society, high income
residential areas often exist close to
the CBD
• Modern cities are expanding beyond
these models—urban sprawl
Other Related Urban Models
Borchert’s Model of Evolution
Bid-Rent Curve
Christaller’s Central Place Theory
Weber’s least Cost Theory
Hotelling’s Locational Interdepence Theory
Vance’s Urban Realms Model
Griffin-Ford Latin America City Model
Borchert’s Model of Evolution
Borchert’s Model of Evolution
• Samuel Borchert studied cities in the United
States 1960
• Linked historical changes to urban evolution
• Borchert’s model defined four classifications of
cities based on transportation technology
Stage 1: Hit growth spurt in “sail-wagon” era of
1730-1830
• Mostly near ports and waterways for
transportation
Borchert’s Model of Evolution (cont)
Stage 2: “iron-horse” cities
• Grew around rivers and canals between 18301870 when railroads and steamboats were
growing rapidly
Stage 3: “steel-rail epoch” (1870-1920)
• During Industrial Revolution when steel industry
blossomed
Stage 4 (1920)
• Linked to air and car travel
Place in your memory bank
Borchert’s Model of Evolution
Bid Rent Curve
Bid Rent Curve
• Bid-Rent curve predicts the following:
• Land prices and population density decline as
distance from the CBD increases
• Bid-rent curves show variations in rent
• Model chooses a point of peak accessibility in the
market (usually CBD)
• Model then shows the cost of land based on
distance from the peak point
• Model states transportation costs increase as
you move away from the market
• Model states that rents usually decrease as
distance increases from the market
Bid Rent Curve
• Different types of land use generate different
bid-rent curve
• Ex: commercial retail, industrial, agriculture,
housing
• Bid-rent curves explain the series of concentric
rings of land use found in the concentric zone
model
• Model shows a pattern in which architectural
form and function of buildings match in each
concentric ring and urban land use
Bid Rent Curve
Can you explain this
graph?
Central Place Theory
This is theory concerned with the
functional importance of places
Central Place
• -is a settlement that provides goods &
services. It can be small (a village) or large
(primate city)
•  all settlements form a link in a hierarchy
Tucson 520,000
Oro Valley 41,000
Marana 38,000
Vail 10,200
Why are there very few
large settlements?
Settlement hierarchy
• Why are there very few large settlements?
• Large settlements need a very large population
(threshold) to support all of their functions
(services)
• Large settlements provide very high order functions
(Tucson Medical Center, Pima County Courts).
• Because these functions are so highly specialized
there is not enough demand to support more than
a few of them
Sphere of influence
• Is the area around each settlement that comes
under it’s economic, social & political control.
Catalina
Marana
38,000
Oro Valley
41,000
Tucson
520,000
Sphere of influence
• The extent of the sphere of influence will
depend upon the spacing size & functions of
the surrounding central places
Catalina
Marana
Oro Valley
Tucson
Central place functions
Function= a service
• These are the goods & services it provides
for local customers & for clients drawn from
it’s wider sphere of influence
Oro Valley
Marana
Tucson
Vail
Population size does not necessarily determine the importance
of the central place
Range & Threshold
• The range of a good or services is the maximum
distance that people are prepared to travel in order
to obtain it. (short distances for a low order item e.g.
newspaper)
• The threshold of a good or services is the minimum
number of people required to support it i.e. 2500doctors surgery, 400-primary school, 25,000-shoe
store, 60,000 for a large supermarket or 100,000large department store/ 1million University
• The more specialized the service the greater the
number of people needed to make it profitable.
Range & Threshold
• Low order items (basic items)= newspaper
• High order items (specialized items)= furniture
• Low order functions (basic services)= corner shop/
primary school
• High order functions (specialized services)= university/
hospital
• Settlements providing low order services = low order
settlements (rural)
• Settlements providing high order services= high
order settlements (urban)
Changes in population size & number of functions
• Settlement sizes change over time (via births, deaths,
migration)
• Settlement functions (services) change over time
• Past 50 yrs in AZ
• Decrease in the number of services available in small
settlements
• Increase in the number of services provided by
larger settlements
Factors that affect a settlements number of
functions
• Settlement depopulation or increased population
• Greater wealth & mobility means some rural
populations no longer visit their own local services
but go further afield seeking services from higher
order settlements
• Domestic changes (freezers) means rural household,
no longer make use of daily low order services (village
meat shop)
Population size does not necessarily determine
the importance of the central place but there is
a strong correlation
The rules of functional
hierarchies
(service)
• 1. The larger the settlements are in size, the fewer
in number they will be
• 2. The larger the settlements grow in size the
greater the distance between them
• 3. As a settlement increases in size the range and
number of it’s functions will increase
• 4. As a settlement increases in size, the number of
higher-order services will also increase (the
services become more specialized)
Walter Christaller’s
Model of Central Places
• Theory states that threshold and range act
as laws that govern the number, size and
distribution of settlements
• When these two factors act together they
create a hierarchical landscape
Walter Christaller’s
Model of Central Places
• Christaller noticed in the flat land of South Germany
that towns of a certain size were roughly equidistant
(uniformly spread)
• He stated that the ideal shape for each towns sphere
of influence should be a hexagon
• Circles either leave gaps (which are unserved by
any central place)
• Or they overlap (meaning one area is served by
too many central places)
Christaller's central place theory
• Christaller stated best shape for a sphere of influence is
a hexagon.
• This shape means consumers still have accessibility
to the highest order central place and its trading
area from all parts of the hexagon
• Christaller's key idea was that customers would go to
the nearest higher order central place to buy goods
and services
• High order central places act like a magnet for
consumers
• He called this phenomenon K=3 (or the marketing
principle)
Christaller's central place theory
• In order to make his theory work Christaller
had to make a few assumptions
• He assumed that each trading area had an isotropic
surface (that the whole area was the same all over)
i.e.
•  the whole area was flat
•  there was only 1 form of transport (and transport
costs were proportional to distance)
•  the population was distributed evenly across the
plain
What's wrong with circles?
What’s wrong with circles
The areas
within the
black dots
shows the
sphere of
influence
(trading area)
of the largest
settlements
The uses of Christaller’s central place model
• The model is often used by governments to
plan the location of new towns and high order
services i.e. hospitals
• It is used by transport authorities to plan
transport routes( so that all areas have equal
access i.e.)
• Businesses can use the model to decide where
to locate a new shop
• However, few real-life regions fit Christaller's
model
Limitations of Christaller's model
The problem with his basic assumptions
• People do not always go to the nearest central place
(they may chose a new edge of city superstore
further away)
• Large areas of flat land rarely exist. Mountains & hills
etc. distort transport routes
• People and wealth are not evenly distributed (if
poorer people live in a certain area & their nearest
high order settlement is expensive then they won’t
visit it)
• Governments often control where new towns are
located, not market forces (i.e. not necessarily where
the demand for goods and services is highest)
Weber’s least Cost Theory
• Alfred Weber (1868-1958) formulated a theory of
industrial location
• He stated industry should locate where it can
• minimize its costs, and therefore maximize its profits.
• Weber’s least cost theory stated a manufacturing
plant should locate based on three cost factors
1. Transportation
2. Labor
3. Agglomeration (where a large number of enterprises
cluster (agglomerate)
Weber’s least Cost Theory
Three Primary Costs
1. Labor: the site chosen must entail the lowest
possible cost of
• A) Moving raw materials to the factory
• B) Finished products to the market. This, according to
Weber, is the most important.
2. Labor:
• Higher labor costs reduce profits
• A factory might do better farther from raw materials and
markets if cheap labor is available (East Asia today)
3. Agglomeration: when a large number of
enterprises cluster (agglomerate) in the same area
(e.g. city), they can provide assistance to each other
through shared talents, services, and facilities (e.g.
Weight Losing Case
• Weight Losing Case
• Weight of the final product is less than the weight of
the raw material going into making the product
• This is the weight losing or BULK-REDUCING
industry
Copper production
steel production
Weight Losing Case
• Weight of the final product is less than
the weight of the raw material going
into making the product
• Increase in transport cost to the left of
the processing plant is the cost of
transporting the raw material from its
source
• Rise in the transportation cost to the
right of the processing plant is the cost
of transporting the final product
• Note the line on the left of the
processing plant has a steeper slope
than the one on the right
Weight Gaining Case
BULK-GAINING
• The final product is heavier than the raw material
that require transport
• Usually this is a case of a raw material such as
water being incorporated into the product
• This is called the weight-gaining or BULK –
GAINING industries
Weight Gaining Case
• Weight gaining case is
illustrated in Figures 5, where
the final product is heavier
than the raw materials that
require transport
• Optimal location of the
processing plant in this case is
at the market
Weight-Gaining and Weight-Losing
• Weight-Gaining
• The finished product(s) weight is more than the raw
materials
• Cost for shipping the finished product are greater than
that of the raw materials.
• Industry location would be the closest to the market!
• Weight-Losing (Also known as bulk-reducing)
• The finished product(s) weight is less than the raw
materials
• Therefore, it cost more to ship the raw materials than
to ship the finished product.
• Industry location would be the closest to the source of
raw materials!
Considerations and limitations for
Weber’s Theory
• Labor costs (labor unions)
• Labor diversity (age, sex,
education, gender, etc)
• Labor movement (indeed
labor does move and change
from place to place)
• Reality of Transportation
Costs
• Land Rent (real estate)
• Tax subsidy
• Pollution (NIMBY factor)
• Long-term Availability of
Resources
• Perishability considerations
• Fragility
• Hazardous materials
• Zoning (residential versus
industrial)
• NAFTA and other special
trade agreements
• Globalization and
Deindustrialization
Hotelling’s Locational Interdepence Theory
• Harold Hotelling (1895 – 1973)
• Was an economist who modified Weber’s Least Cost
Theory in 1929
• Hotelling focused on the revenue side of profits, unlike
Weber who focused on the cost side of profits
• Hotelling’s theory of locational interdependence
asserts that industries choose locations based upon
where their competitors are located
• In other words, industries do not make isolated decisions
without considering where other, related industries
already exist
• Locational interdependence says that:
• Location of an industry can not be understood without
reference to the location of other similar industries
Hotelling’s Locational Interdepence Theory
• Harold Hotelling (1895 – 1973)
• An economist who modified Weber’s Least Cost
Theory in 1929
• Hotelling focused on the revenue side of
profits, unlike Weber who focused on the cost
side
• Hotelling’s theory of locational
interdependence asserts that industries choose
locations based upon where their competitors
are located
Hotelling’s Locational Interdepence Theory
• Locational interdependence says that:
• Location of an industry can not be understood without
reference to the location of other similar industries
• Producers/suppliers will monopolize as many
consumers as possible
• They seek SPATIAL MONOPOLY, hence LOCATIONAL
INTERDEPENDENCE
• Industries do not make isolated decisions without considering
where other, related industries already exist
• Hotelling’s Assumptions:
• Production costs are uniform, product selection is
uniform, and demand is uniform
Hotelling Beach
Ice Cream Vendors Interdependent Location in Linear Market
Urban Realms Model
• Developed by James Vance in 1964
• Urban realms model says
• Suburban downtowns have become
independent functioning “urban realms”
• All the amenities needed for living are now
located in the suburban downtown
• Developed to explain suburban regions that
were functionally tied to mixed-use
suburban downtowns with relative
independence from the CBD
Edge Cities
• Self-Sufficient urban areas within a greater
metropolitan complex
• Often develop on highway exits
• Edge cities with growth of highways lead to
explosive industrial growth referred to as
urban sprawl
• Urban sprawl….the diffusion of urban land
use and lifestyle into formerly nonurban,
often agricultural lands
Urban Realms (and Edge Cities) of Los Angeles
Latin America City Model
(Griffin-Ford Model)
• Larry Ford & Ernest Griffin created a model of the
pattern of urban growth in Latin America (1980)
Griffin-Ford Latin America City Model
• Larry Ford & Ernest Griffin developed a
model of urban growth in Latin America
• Model contained elements of Latin
American culture
• Contained imprints of colonization and
globalization
• Prominent plaza & heavy growth around the
CBD
Features of Latin America City Model
• Model is representative of almost all
major cities in Latin America.
• Model shows most cities have a
central business district
• Model shows at least one dominant
elite residential sector and a
commercial spine.
• These areas surrounded by a series
of concentric zones
• Residential quality decreases with
distance from the CBD
Features of Latin America City Model
• Model has a zone of maturity
populated with services and
wealthier population
• Model has a zone of squatter
settlements; recent urban migrants
set up makeshift housing
• Model has a zone of in situ accretion
(a zone that shows signs of
transition to a zone of maturity
Other Important Models
Rostow’s Stages of Economic Development
Wallerstein’s World System’s Theory
Von Thunen’s Model of Agricultural Land Use
Demographic Transition Model
Epidemiologic Transition Model
Gravity Model of Spatial Interaction
Zelinsky Model of Migration Transition
Ravenstein’s Laws of Migration
Rostow’s Stages of Economic Development
Rostow’s Stages of Economic Development
• Published by American economist Walt
Whitman Rostow in 1960.
• Model postulates that economic growth
occurs in five basic stages, of varying length
• Five stages of development
• These are applicable to all societies, but viewed
from a market perspective
1.
Traditional society
2.
Preconditions for take-off
3.
Take-off
4.
Drive to maturity
5.
Age of High mass consumption
Rostow’s Stage #1: The Traditional Society
• In a traditional society people have little
collective ability to raise their economic
productivity
• They lack the technical and scientific
knowledge
• They devote a high proportion of their
resources to farming
• Political power is concentrated in the hands
of the landowners
• Family and inheritance are highly valued
Rostow’s Stage #2: Preconditions for Takeoff
• It takes time to alter a traditional society
because old beliefs are difficult to challenge
• Signs of the preconditions for takeoff
•
•
•
•
•
Growing acceptance of technology
Rapidly increasing population
The growth of education
Rise of banks
Growing efficiency of farming
• Diminishing number of farmers must be able to
• Feed swelling urban populations
• Prevent unemployment in the towns by demanding
industrial products
Rostow’s Stage #3: Takeoff
• Takeoff occurs when the bulk of society
comes to accept and favor the idea of change
• Output per person increases enormously, and
real wages rise
• Country as a whole benefits from advances in
a few leading industries
• Widespread diffusion of literacy occurs from
compulsory education
• Health care improves and life expectancy
increases
Rostow’s Stage #4: Drive to Maturity
• This is a long period of sustained change
• Technology gradually spreads throughout all
areas of economic activity
• Society adapts to the changes
• universal education and medical facilities are
created
• Democracy becomes established
• Government begins to appropriate larger
proportions of the national wealth
• Old ways die, people begin to fell free in their
choice of beliefs
Rostow’s Stage #5: Age of High Mass Consumption
• During this age, the leading sectors shift more
toward services
• Those of finance, information and government
• Material production continues
• Social welfare becomes a higher value
• People talk of the quality of life rather than of
the standard of living
• There is a broad range of choice, not only for
the individual, but for the whole of society
Remember the stair steps
Limitations of Rostow’s Model
• 1. Determinants of a country's stage of economic
development are usually seen in broader terms i.e.
dependent on:
• Quality and quantity of resources
• Country's technologies
• Countries institutional structures e.g. law of contract
• 2. Rostow explains the development experience of
Western countries, well.
• However, Rostow does not explain the experience of
countries with different cultures and traditions e.g. Sub
Sahara countries which have experienced little
economic development.
• Comment: Rostow’s Stages of Economic
Development was essentially a statement
repudiating The Communist Manifesto!
Wallerstein’s World System’s Theory
• Immanuel Wallerstein’s Model was developed
in the 1970s
• Wallenstein was expanding the dependency
theory
Four Major Aspects to Wallenstein’s Theory
1. Developing countries are not exploited by
individual countries
• They are exploited by the whole capitalist,
profit-seeking system
• He names this “A Modern World System”
(MWS)
• The MWS is a unified system of capitalism
Four Major Aspects to Wallenstein’s Theory
2. There are three zones in the MWS
• The core/developed nations – these control world
trade and monopolize manufactured goods
• The semi-peripheral zone e.g. Brazil, South Africa,
urban areas like the core but large areas of rural
poverty like the periphery
• The peripheral countries e.g.. Most of Africa –
they provide primary products for both the semi
periphery and the core
Four Major Aspects to Wallenstein’s Theory
3. Wallerstein’s model is dynamic
• It allows for movement and change
• Countries are ‘socially mobile’ they can move in
from the periphery into the semi periphery
• Examples are the Asian tigers (Singapore,
Taiwan, South Korea)
• Also they can move from the core to the semi
periphery (Britain)
Four Major Aspects to Wallenstein’s Theory
4. Wallerstein’s has similarities to the
dependency theory
• Both show how surplus value created in the
periphery is appropriated (taken without
permission) by the semi periphery and especially
the core
• Both see the origins of exploitation of some
countries by others to have originated in slavery,
colonialism and neo-colonialism
Wallenstein’s World Systems Theory Weaknesses
• Wallerstein does not look at internal factors
(E.g. mismanagement and corruption in the
LDC’s)
• Methodology is too vague and unscientific,
“core” etc. cannot be clearly operationalized
Wallenstein’s World System Theory Strengths
• Wallerstein was one of the first to recognize
“globalization’ of the world and the
international division of labor as the basis of
global inequality”
Von Thünen’s Model of Agricultural Land Use
• John Von Thünen was farmer and amateur
economist
• Model was created before industrialization in
1826
Von Thünen’s Model of Agricultural Land Use
• Based on the layout of
Rostock, Germany
• Noticed a pattern of 4 rings
developed around the
central city.
• Each ring was a different
type of agriculture.
• Created before highways,
railroads, factories, etc.
Von Thunen’s Six Assumptions
1. The city is located centrally within an “isolated
state" which is self sufficient and has no external
influences
2. The Isolated state is surrounded by an unoccupied
wilderness
3. The land of the state is completely flat and has no
rivers or mountains to interrupt the terrain.
4. The soil quality and climate are consistent
throughout the state
5. Farmers in the “isolated state” transport their own
goods to market via oxcart, across land, directly to
the central city. Therefore, there are no roads.
6. Farmers act to maximize profits
Von Thunen’s Hypothesis
• Four rings of agricultural activity surround the city
• First Zone: dairying and intensive farming occur in the
ring closest to the city
• Since vegetables, fruit, milk and other dairy products
must get to market quickly, they would be produced
close to the city
• Second Zone: forest resources (timber and firewood)
would be produced for fuel and building materials in
the second zone
• Before industrialization (and coal power), wood (forest)
was a very important fuel for heating and cooking.
• Wood is very heavy and difficult to transport so it is
located as close to the city as possible.
Von Thunen’s Hypothesis
• Third zone consists of extensive fields crops
such as grains for bread
• Grains last longer than dairy products and are
much lighter than fuel
• They reduce transport costs and can be located
further from the city
• Fourth Zone: ranching (livestock farming) is
located in the final ring surrounding the central
city
• Animals can be raised far from the city because
they are self-transporting.
• Animals can walk to the central city for sale or for
butchering
Another Look
Strengths and Weaknesses of
Von Thünen’s model
• Von Thünen did not consider modern
technology that had yet to be invented in his
time
• Refrigerated cars for the transportation of dairy
products
• Transportation of animals by rail which is faster
than having them being grazed into the city
• His ideas do tend to apply in LDCs where
modernization has not taken place
Strengths and Weaknesses of
Von Thünen’s model
• Von Thünen model is a good example of the
balance between land cost and transportation
costs
• Closer you get to the city, the higher the price of
land
• Commercial farmers today have to balance the cost
of transportation, land, and profit to produce the
most cost-effective product for their market
• Bid Rent Curve applys to Von Thünen model
Demographic Transition Model-the Basics
• There are four stages of transition from an
agricultural subsistence economy to an
industrialized country
• Demographic patterns move from extremely
high birth and death rates to low birth and
death rates
• In the process population growth rates
skyrocket and then fall again
• The crude death rate first falls because of the
influx of better health technology, and then the
birth rate gradually falls to match the new social
structure
The Classic Demographic Transition
Stage 1
Stage 2
Stage 3
Stage 4
Birth rate
Natural
increase
Death rate
Time
Note: Natural increase is produced from the excess of births over deaths.
This chart explains the typical changes in the birth rate and
death rate that happen as a country industrializes
(including the U.S.).
Stage 1
Stage 2
Stage 3
Stage 4
Birth rate
Natural
increase
Death rate
Time
Note: Natural increase is produced from the excess of births over deaths.
It models the classic demographic transition. This shift
occurred throughout Europe & North America, in the 19th
and early 20th centuries, and started in many developing
countries in the middle of the 20th century.
Stage 1
Stage 2
Stage 3
Stage 4
Birth rate
Natural
increase
Death rate
Time
Note: Natural increase is produced from the excess of births over deaths.
Stage 1: The trend of high birth and death rates
(and minimal population growth)
Stage 1
Stage 2
Stage 3
Stage 4
Birth rate
Natural
increase
Death rate
Time
Note: Natural increase is produced from the excess of births over deaths.
Stage 2: Starts when the death rate begins to drop for years,
and often decades, until the beginning of its stabilization at a
new, low level. (In Europe, this stage happened because of
improved health and living conditions and marked beginning a
period of rapid population growth.)
Stage 1
Stage 2
Stage 3
Stage 4
Birth rate
Natural
increase
Death rate
Time
Note: Natural increase is produced from the excess of births over deaths.
Stage 3: Next the birth rate falls to about the same,
low level as the death rate.
Stage 1
Stage 2
Stage 3
Stage 4
Birth rate
Natural
increase
Death rate
Time
Note: Natural increase is produced from the excess of births over deaths.
Stage 4: With birth and death rates at similar low
levels, the equilibrium of slow population growth is
regained.
Stage 1
Stage 2
Stage 3
Stage 4
Birth rate
Natural
increase
Death rate
Time
Note: Natural increase is produced from the excess of births over deaths.
Demographic Transition Model – Looking
at The Whole Picture
Epidemiologic Transition Model
• Disease vulnerability shifts in patterns
similar to the Demographic Transition Model
• Stage I: Pestilence and Famine
• Infectious and parasite diseases were principle
causes of death along with accidents and attacks
by animals and other humans.
• Thomas Malthus called these caused of death
“natural checks”
• Most violent Stage I epidemic was the Black
Plague(bubonic
Epidemiologic Transition Model
• Stage II: Receding Pandemics
• Improved sanitation, nutrition, and medicine
reduce the spread of infectious diseases e.g.
Industrial Revolution
• Death rates did not improve immediately and
universally during the early years of the Industrial
Revolution.
• Poor people who crowded into Industrial Cities
had high death rates due to Cholera
Epidemiologic Transition Model
• Stage III: Degenerative Diseases
• Associated with the chronic diseases of aging
• Heart disease and cancer
• Sub-Saharan Africa and South Asia have low incidences
of cancer primarily because of low life expectancy
• Stage IV: Delayed Degenerative
• Life expectancy of older people is extended through
medical advances
• Cancer medicines, bypass surgery, better diet, reduced
use of tobacco, and alcohol
• However, consumption of non-nutritious food and
sedentary behavior have resulted in an increase in
obesity in this stage
Gravity Model: The Theory
• Spatial Interaction - The closer together
phenomena are the easier it is for interaction to
take place.
• Spatial Interaction - Assumed to decline with
increasing distance.
• Distance Decay - The result of declining
interaction - termed friction of distance.
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Gravity Model of Spatial Interaction
• Gravity Models have been used in economics and
social sciences since 1929
• Gravity Models allow for the measurement of
spatial interaction as a function of distance
• Gravity Model when applied to migration
• Larger places attract more migrants than do smaller
places
• Destinations that are more distant have a weaker pull
effect than do closer opportunities of the same
caliber
• The volume of migration is inversely proportional to
the distance travelled and directly proportional to the
relative sizes of the origin and destination places
Zelinsky Model of Migration Transition
• Model claims that the type of migration that
occurs within a country depends on how
developed it is or what type of society it is.
• The essential feature of the model is based
on Rostow’s stages of economic growth.
• As modernization proceeds different patterns
of migration emerge.
Zelinsky Model of Migration Transition
Phase 1: Pre-modern traditional society:
• This is before the onset of the urbanization, and
there is very little migration.
• Natural increase rates are about zero.
Phase 2: Early transitional society:
• There is “massive movement from countryside to
cities... as a community experiences the process
of modernization”.
• There is “rapid rate of natural increase”.
Zelinsky Model of Migration Transition
Phase 3: Late transitional society:
• Urban-to-urban migration surpasses the rural-tourban migration
• Rural-to-urban migration continues but at
waning or relative rates”
• Phase 4: Advanced society:
• Movement from countryside to city continues
but is further reduced
• Vigorous movement of migrants from city to city
and within individual urban agglomerations is
observed
• There is slight to moderate rate of natural
increase or none at all
Zelinsky Model of Migration Transition
• Phase five: Future super-advanced society:
• Nearly all residential migration is of the
interurban and intraurban variety
• There is a stable mortality pattern slightly below
present levels
Ravenstein’s Laws of Migration
• In 19th century E.G. Ravenstein used data
from England to outline a series of laws
explaining patterns of migration
• His laws state that migration is impacted by
push and pull factors
• Unfavorable conditions, such as oppression
and high taxes, push people out of a place
• Attractive opportunities, pull factors, cause
them to migrate into regions
• Better economic opportunities are the chief
cause of migration
Ravenstein’s Laws of Migration
• Migration occurs in multiple stages rather than
one move
• The majority of people move short distances
• Those who migrate longer distances choose bigcity destinations
• Urban residents are less migratory than rural
residents
• For every migratory stream, there is a counter
stream
• Factors such as gender, age, and socio-economic
level influence a person’s likelihood to migrate