How do you calculate population growth?
Human population growth depends on the rate of natural increase, or the fertility rate minus the mortality rate, and net migration.
The basics of demography can be reduced to this formula:
- (Births – Deaths) +/- ( (In-Migration) – (Out Migration)) = Population Change
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Natural Increase
One of the things we need to know in order to calculate the demographic balancing equation is natural increase, or the population change from births and deaths.
Calculating this is pretty easy - just subtract the number of deaths from number of births; that's how much your population increased or decreased from natural causes.
We can get this infor.
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The Demographic Balancing Equation
Demographics can tell us a lot of information, but counting every single member of the population takes a lot of work.
Really, the government only does this once every ten years with the national census, the most thorough demographical record of a nation.
This counts as much as it can, but in between those ten years, it's still important to know ho.
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What is a general demographic equation?
A general demographic equation is a starting population plus the change in population due to natural increase plus the change in population due to migration.
For general population, this would be equal to the total starting population plus (births minus deaths) plus (immigration minus emigration).
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What is the difference between population ecology and demographic analysis?
In the labor force, demographic analysis is used to estimate sizes and flows of populations of workers; in population ecology the focus is on the birth, death, migration and immigration of individuals in a population of living organisms, alternatively, in social human sciences could involve movement of firms and institutional forms.
Demographic gravitation is a concept of social physics, introduced by Princeton University astrophysicist John Quincy Stewart in 1947.
It is an attempt to use equations and notions of classical physics, such as gravity, to seek simplified insights and even laws of demographic behaviour for large numbers of human beings.
A basic conception within it is that large numbers of people, in a city for example, actually behave as an attractive force for other people to migrate there.
It has been related to W.
J.
Reilly's law of retail gravitation, George Kingsley Zipf's Demographic Energy, and to the theory of trip distribution through gravity models.
