Class Demography

java.lang.Object

org.episteme.social.sociology.Demography

All Implemented Interfaces:

Serializable

public final class Demography
extends Object
implements Serializable

Provides mathematical models for age-structured populations and demographic transitions. Includes implementations for Leslie Matrix projections and standard demographic ratios.

Since:

1.0

Version:

1.1

Author:

Silvere Martin-Michiellot, Gemini AI (Google DeepMind)

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final record	Demography.PopulationPyramid	Data structure representing the age and gender distribution of a population.

Method Summary

Modifier and Type	Method	Description
static Real	childWomanRatio(int children0to4, int women15to49)	Calculates the Child-Woman Ratio (CWR).
static int	estimateTransitionStage(Real birthRate, Real deathRate)	Estimates the demographic transition stage based on birth and death rates.
static Real	netReproductionRate(Vector<Real> ageFertility, Vector<Real> femaleSurvival)	Calculates the Net Reproduction Rate (NRR).
static Vector<Real>	projectLeslie(Vector<Real> population, Vector<Real> fertility, Vector<Real> survival)	Performs a Leslie Matrix projection to estimate the next generation's population.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

projectLeslie

public static Vector<Real> projectLeslie(Vector<Real> population,
 Vector<Real> fertility,
 Vector<Real> survival)

Performs a Leslie Matrix projection to estimate the next generation's population. P(t+1) = L * P(t).

Parameters:

population - current population vector by age SociologicalGroup (Real)

fertility - fertility rates per age SociologicalGroup (Real)

survival - survival probabilities per age SociologicalGroup (Real)

Returns:

predicted population vector for the next time step

childWomanRatio

public static Real childWomanRatio(int children0to4,
 int women15to49)

Calculates the Child-Woman Ratio (CWR). CWR = (Children 0-4 / Women 15-49) * 1000.

Parameters:

children0to4 - number of children aged 0-4

women15to49 - number of women aged 15-49

Returns:

the CWR as a Real number

netReproductionRate

public static Real netReproductionRate(Vector<Real> ageFertility,
 Vector<Real> femaleSurvival)

Calculates the Net Reproduction Rate (NRR). NRR = Sigma (Fertility_i * femaleSurvival_i).

Parameters:

ageFertility - fertility rates per age cohort

femaleSurvival - female survival probabilities per age cohort

Returns:

the NRR as a Real number

estimateTransitionStage

public static int estimateTransitionStage(Real birthRate,
 Real deathRate)

Estimates the demographic transition stage based on birth and death rates.

Parameters:

birthRate - birth rate per 1000 individuals

deathRate - death rate per 1000 individuals

Returns:

the transition stage (1 to 5)