Demographic models

1. Demographic models Lecture 1.A model in Science. Aim and limitation of models. Modeling in demography. Connection of modeling with methods, language, processes in the complementary sciences. Examples. Classification of models. Continuous vs discrete models. Determinate vs stochastic models. Macromodels, micromodels. Linearity – nonlinearity of the system. Static vs dynamic models. Models of population dynamics.

2. Demographic models • The model is a set of concepts built up in our heads on the project, with terms and relationships that reflect domain insight. These terms and interrelationships provide the semantics that is tailored to the domain while being precise enough for our study. • Physical model of the object • Scale model • Conceptual model – model that uses ideas for representation of another ideas • Model of the system • Computer models • Model of data • Model of ecosystem • Mathematical model • Regional model (socio-economic) A model in Science

3. Demographic models A model in Science. Aims and restrictions of models. • Main signs: • A method of scientific study • Abstraction from random, minor, specific processes, events, properties • Hypothesis testing and checking the assumptions • Formulation and grounding of main statements of the theory • Opportunities of verification and adjustment • Formal representation (scheme, equation, graph) of our current understanding of the object

4. Demographic models Modeling in demography Models allow to conduct “pure” and “bloodless” experiments over the phenomena that do not exist in the pure form and experiments with them are simply impossible. (Oleg Staroverov) Модели позволяют провести «чистые» и «бескровные» эксперименты над явлениями, которые в чистом виде не существуют и эксперименты над которыми просто невозможны. (О.В.Староверов) Example. Model of stable population. Simplifications: constancy of population indicators, no migration, independence of demographic events of one person from another persons.

5. Demographic models Modeling in demography. Connection of models with methods, language, and processes in the complementary sciences. Theory of probability:independence of events, probability of occurrence Theory of matrices:vector length, transition matrix Physics: conservation laws Biology: age, life, vital events Sociology : opinions and intentions of people Economy: factors of demographic behavior - income, standard of living, labor productivity Medicine, health care:morbidity, cause of death System analysis:subsystem, feedback, interaction, stability

6. Demographic models Modeling in demography. Connection of models with methods, language, and processes in the complementary sciences. Statistics:? Computer science:? History: ? Ethnology: ? Geography: ? Juridical Science: ? Ecology:? Linguistics:? Sexology:? Gerontology:? Think together!

7. Demographic models Modeling in demography. Connection of models with methods, language, and processes in the complementary sciences. Statistics:accounting, frequency, registration, tabulation, census Computer science:database, file, data processing, data format History: historical events, historical factors, territorial changes Ethnology: ethnicity, people, ethnic group Geography: city, urban, rural population, region, settlement, country Juridical Science: Family Code, citizenship, naturalization Ecology:climate, pollution, global warming Linguistics:thesaurus, dictionaries, encyclopedias Sexology:sexual behavior, sexual education, contraception Gerontology:aging, oldest-old, centenarians, supercentenarians

8. Demographic models Modeling in demography. Connection of models with methods, language, and processes in the complementary sciences. . Population genetics Natural selection, mutagenesis, genetic drift, subpopulations, migration, adaptation, evolution, genogeography

9. Demographic models Modeling in demography. Connection of models with methods, language, and processes in the complementary sciences. . Genealogy – systematic collection and analysis of data on origin, succession, relationship family ties, relatives, population registers, vital events, certificates (birth, death, marriage)

10. Demographic models Modeling in demography. Connection of models with methods, language, and processes in the complementary sciences. . Cybernetics: optimal control, regulation, reaching the desired level of indicator or desired structure, optimum of population, positive or negative feedback

11. Demographic models Modeling in demography. Connection of models with methods, language, and processes in the complementary sciences. Epidemiology:Initiation , propagation, transmission of diseases. Territory, subpopulation, population method, prevention and projection, geographical information systems Author: Emilio Gómez Fernández

12. Demographic models Classification of demographic models Continuous: phase variables of the model, independent variables (age, duration of residence, marriage duration,…) – have continuous measures. Discrete: phase variables of the model, independent variables are the integer ones, belong to the finite set of values. Advantages, problems, shortcomings Автор: Emilio Gómez Fernández

13. Demographic models Classification of demographic models. Deterministic and stochastic models Deterministic: population processes are characterized by the direction and intensity only. No randomness. Stochastic: demographic events are considered as a random process. Advantages, problems, shortcomings Автор: Emilio Gómez Fernández

14. Demographic models Classification of demographic models. Deterministic and stochastic models Example of dynamics of two subpopulations in deterministic and stochastic versions. Автор: Emilio Gómez Fernández

15. Demographic models Classification of demographic models. Macromodels, micromodels. Macromodel: variables of the model describe the scale, dynamics, and direction of mass socio-demographic processes Micromodel: the number and type of socio-demographic events are obtained as a set of individual cases which take place with the person, marital pair, family, or household Автор: Emilio Gómez Fernández

16. Demographic models Classification of demographic models. Static versus dynamic models Static model describe the age structure, regional distribution, marital composition, distribution of families by types, etc. for a fixed moment as function of demographic indicators Dynamic model defines the direction and speed of demographic processes and structures, their changes in course of time as a function of the initial state, indicators, and factors of these processes Автор: Emilio Gómez Fernández

17. Demographic models Classification of demographic models. Linearity – Nonlinearity of the system Linear model assumes that the number of events of a given demographic process is proportional to the size of socio-demographic group. Nonlinear model assumes that the speed or direction of demographic process significantly depends upon the the size of socio-demographic group. Автор: Emilio Gómez Fernández

18. Demographic models Classification of demographic models. Models of population dynamics. Stationary population Stable population Models of demographic transition Matrix model of population reproduction Model by Sergey Kapitza Автор: Emilio Gómez Fernández

19. Demographic models Another examples: mathematics, global world dynamics, econometrics, assurance, actuary, population mathematics, biometrics, anthropologybiodemography, historical demography, economic demography.