The Demopædia Encyclopedia on Population is under heavy modernization and maintenance. Outputs could look bizarre, sorry for the temporary inconvenience
Multilingual Demographic Dictionary, second unified edition, English volume
73
Disclaimer : The sponsors of Demopaedia do not necessarily agree with all the definitions contained in this version of the Dictionary. The harmonization of all the second editions of the Multilingual Demographic Dictionary is an ongoing process. Please consult the discussion area of this page for further comments. |
Go to: Introduction to Demopædia | Instructions on use | Downloads |
730
A demographic model ^{1} consists of a theoretical construct representing the evolution of a population (of individuals, couples, families, households, etc.) and its structure on the basis of its initial state and the effect of various demographic variables (such as fertility, fecundability, mortality, etc.). In a static model ^{2}, these variables remain constant; in a dynamic model ^{3}, they are allowed to change over time. A further distinction is made between deterministic models ^{4} which assign functional relations between definite values of the variables, as if the studied population were infinitely large, and stochastic models ^{5} or probabilistic models ^{5} which consider the probability of various events occurring to individuals over the duration of the process under study. The model may be set out in mathematical formulas or take the form of a simulation ^{6} where specific values of the variables are included in a system of relations. Macrosimulations ^{7} may for example involve population projections made by the component method (720-5). In microsimulations ^{8}, events are made to occur randomly to individuals or groups over time according to sets of probabilities assigned to the variables in the model.
- 1. The word is also used as an adjective in such expressions as model tables.
* * *
Go to: Introduction to Demopædia | Instructions on use | Downloads |