Denominators Flashcards
What is natural increase?
Births - Deaths
What is net migration?
In - Out
What is a population?
1) All the inhabitants of a given area considered together
2) In sampling: the whole collection of units from which a sample may be drawn
What is the total dependency ratio? What is the interpretation?
(P0-14 + P65+)/P15-64 x 100
At TDR > 100, there are more dependent people than workers
Describe populations in each of the stage
STAGE 1: EXPANDING
- also “zero growth” and “preindustrial”
- high birth rate
- high death rates (so rapid fall in each upward age group)
- short life expectancy
- shape: ‘ski slopes’ triangle
STAGE 2: EXPANDING
- also “quick growth” or “developing”
- high birth rate
- falling death rate
- slightly longer life expectancy
- shape: triangle
STAGE 3: STATIONARY
- also “slow growth” or “young developed”
- declining birth rate
- low death rate
- longer life expectancy
- shape: half-oval
STAGE 4: CONTRACTING
- also “no growth” or “old developed”
- low birth rate
- low death rate
- higher dependency ratio
- longer life expectancy
- shape: truncated circle
Rate of natural increase (RNI)?
RNI = (crude birth rate/1000) - (crude death rate/1000) x 100
Doubling time?
70/Rate of Natural increase
Growth rate?
r = (lnP2 - lnP1)/t
Doubling time?
t = ln2/r
What are the characteristics of a stable population?
- Constant age distribution and growth rate
- Constant birth and death rates
- Population can still change size
What is a stationary population?
- Growth rate is zero
- Age distribution and SIZE of population are constant
Sex ratio formula?
males/#females x 100
What is primary sex ratio?
Sex ratio at conception (1.15-1.20)
What is secondary sex ratio?
Sex ratio at birth (1.05)
What is tertiary sex ratio?
Sex ratio in adulthood and old age (1 at 30 yrs; 0.25 at 100 years)
Crude birth rate formula?
births/midyear pop x 1000
General fertility rate formula (GFR)?
births/midyear fem15-49 pop x 1000
Age-specific fertility rate formula?
fx = Bx/Wx x 1000
Total fertility rate formula (TFR)? Interpretation?
TFR = (interval size) * SUM(age-specific fertility rates)
children expected to be born to an individual woman over the duration of her childbearing years
What Total Fertility Rate (TFR) is needed for replacement of the population?
Depends on life expectancy
If LE = 25: 5.2
If LE = 75: 2.1
Gross Reproduction Rate (GRR) formula? Interpretation?
GRR = TFR * pw
*pw = % of female births in pop
Average # of female offsprings. If <1 insufficient reproductivity for replacement; >1 sufficient for replacement; =1 zero growth
Net reproduction rate?
GRR adjusted for mortality in women of childbearing ages - best indicator for long term potential population growth
Cohort fertility rate (CFR)?
CFR = (interval size)*SUM(age-specific fertility rate) for one birth cohort
What is fecundity?
Has to do with contraception, sterilization, disease-specific, etc.
