Learning outcomes To understand what the rank Size rule is and the pattern that it tries to outline
Rank Size Rule This is an attempt to find a numerical relationship between population size of settlements within an area such as a country or county Settlements are ranked in descending order of population size, with the largest city first
Assumptions The 2 nd ranked city will have 1/2 the population of the 1 st The 3 rd ranked city will have 1/3 population of the 1st The 4 th ranked city will have a ¼ population of the 1st ranked city
Example The largest city has a population of 1,000,000 The 2 nd largest city: 1,000,000/2= 500,000 The 3 rd city: 1,000,000/3= 333,333 The 4 th city: 1,000,000/4= 250,000 And so on….
Formula This allows us to express the rank size rule as: Pn= Pl /n (or R) Pn= The population of the City Pl= The population of the largest city N (or R)= The rank size of the city See graph Page 404/405 Brazil e.g.
Variations from the Rank Size Rule It is rare to find a close correlation between the city size of a country and the rank size rule
Primate City This is found where the largest city (often the capital) completely dominates a country or region The population size will be many times greater than that of the 2 nd or 3 rd city
Example of Primate City: Buenos Aires Populations in thousands: Buenos Aires: 10,990 Cordoba: 1198 Rosario: 1096 Mendoza: 775 La Plata: 640 San Miguel de Tucuman: 622
Binary Distribution Occurs where there are 2 very large cities of almost equal size within the same country. One may be the capital and the other a major port or industrial centre Examples: Spain- Barcelona and Madrid
Exceptions to the rule Rank size rule is more likely to operate in a country that is developed or urbanised for a long time Large in size Stable economic and political organisation Primate distribution is likely to occur in countries that are small, less developed and only recently urbanised