Transcript Presentazione di PowerPoint - Regionalna Agencija za

WP5.4 – Transnational transfer of experiences
Overview of methodology for population
projections
Jana Suklan
25.9.2014 – 27.9.2014 Piran
Objective:
 demographic trends: analysis and harmonization of the
knowledge base
 provide key aspects of demographic change in
population structure age/sex/citizenship
Outputs
 population projections methodologies
 policy scenarios methodologies taking into account
migration movements
Population projection methods overview
Source: Data courtesy of US Census Bureau International Programs
.
(Wang & Vom Hofe, 2007, 56)
Cohort-component method
 accounts for the components of population change
 uses sex-age-specific population cohorts
 Subdividing cohorts further (level of detail)
(Wang & Vom Hofe, 2007, 56)
Method origins: Carnan, 1985; Bowley, 1924; Whelpton, 1928
Components of population change are:
 population (P)
 births (B)
 deaths (D)
 in-migrants; IM
 out-migrants; OM
Demographic balancing equation:
population grows
population declines
Source: http://www.ukisfull.co.uk/
Unique definitions of demographic terms
were provided by MMWD partner.
Natural population increase or decrease – fertility
 fertility rates vary geographically, culturally, and over time
 variations may result of a combination of complex economic,
social, and other factors
Total Fertility Rate (TFR): refers to average number of births per
woman.
(Wang & Vom Hofe, 2007, 68)
Natural population increase or decrease – mortality
 people dying from one time period to the next
 expressed in the form of mortality or survival rates
 Life Tables Survival Rates by age and sex - these tables
report probabilities of dying between ages x and x+1 or
number of people surviving to age x
(Wang & Vom Hofe, 2007, 68)
Migration




People move within the same county: internal migration
People move to a different county: international migration.
positive net migration rates - people move into the region
less attractive regions show negative net migration rates
(Wang & Vom Hofe, 2007, 77)
Cohort-component method
Why is the population changing?
Are the reasons for the expected changes mainly driven by births,
deaths, and/or in- and out migration?
How is the population changing?
Is the population aging?
Is the racial composition of the population changing?
(Wang & Vom Hofe, 2007, 127)
Method origins: Carnan, 1985; Bowley, 1924; Whelpton, 1928
Cohort-component method
1
• Mortality
2
• Net Migration
3
• Fertility
(Wang & Vom Hofe, 2007, 115)
The Fertility Component
STEP 1
STEP 2
STEP 3
• project the number of births per female age cohort;
• aggregate all births and allocate this aggregated total
between male and female births;
• apply the survival rates to the cumulated of all live births
(Wang & Vom Hofe, 2007, 120)
Bringing All
Components Together
Salzburg University of Applied Sciences (SUAS): Study visit material
 Projections:
• divide the population into age and sex cohorts (subdivision:
BASIC
• divide the population into age and sex cohorts (subdivision:
EXTENDED
Data requirement:
 Age/sex structure of the initial population separetedly for total
and foreign population;
 A table of mortality
 A structure of fertility by age
 A structure of migration by sex and age
Projection assumptions:
 Fertility: average of the last 10 years
 Mortality: linear extrapolation of life expectancy of the last 10
years
MMWD, Methodological references
Scenarios for BASIC PROJECTION:
1) „Closed population scenario“ zero (net) migration
2) Constant migration (average of the last 10 years)
3) Average migration trends for the period 2009-2012
(economic crisis)
MMWD, Methodological references
EXTENDED PROJECTION: education attainment/households
1) STATIC APPROACH: static rates are applied to the projected
population without taking into account the internal dynamics
2) DYNAMIC APPROACH: capable of controlling a priori
information and assumptions influencing the dynamics
MMWD, Methodological references
Projection of population by educational attainment
 applying tables of proportions (static method) or
 cumulative proportions and
 transition probabilities (dynamic method) obtained by level
of educational attainment to the main projections of population
age/sex/citizenship.
MMWD, Methodological notes
Data requirements to compute transition probabilities:
Variables from Labour Force Survey (at least two surveys):
1) Highest level of education attained (ISCED classification)
2) Sex
3) Age
4) Citizenship
MMWD, Methodological references
Procedure to compute transition probabilities:
1) choose the number of categories
Level 0-2
Level 3
Level 4
Level 5-6
MMWD, Methodological references
2) decide the size of age classes (5-year age classes)
15-19 years
20-24 years
25-29 years
30-34 years.
MMWD, Methodological references
3) Compute frequency tables of sample population by citizenship,
sex, age and level of education
4) Obtain percentage distribution tables of population by level of
education need to be computed for each age class
5) Obtain percentage retro-cumulative distribution tables by crosssection.
6) Compute transition probabilities.
MMWD, Methodological references
Projections of family structure „Headship rate method“
Household type by household size
Household type merged by age of reference person
MMWD, Methodological notes
Family typology:
--One-person households
--Multi-person households
Households without nucleus
Couple without children
Couples with children
Mothers with children
Fathers with children
Households with two-or-more nucleus
MMWD, Methodological notes
Data requirements - Labour Force Survey:
1) number of heads of household
2) number of individuals resident population in household
From here headship specific rate is determined. Headship rates will
be computed by type of family and the family distribution by size
and typology.
MMWD, Methodological notes
Literature:
MMWD, Methodological references for population projections, October 2013.
MMWD, Methodological note for demographic projection in Emilila-Romagna.
MMWD, Practical Tool Projections of the population by level of education in EmililaRomagna, November 2013.
Goujon, A., Lutz, W., & Sanderson, W. (2004). Report on projections by level
of education (Future human capital: population projections by level of education). The end of
world population growth in the 21st century. New challenges for human capital formation and
sustainable development, 121-141.
Wang, X., & Vom Hofe, R. A. (2007). Research methods in urban and regional planning:
Springer.