S4: Demography Flashcards
Def of Demography
Scientific study of human population, Including:
- Population census
- Population pyramid
- Overpopulation problem
- Fertility indices
Def of Population census
- Enumeration of all persons in the country at specified time to collect demographic and socioeconomic data.
How Often is Population census done?
Every 10 years
at Time of minimal movement & done in winter not in summer
Value of Population census
❶ Full description of population.
❷ Data for:
Statistical indices.
Community programs (including health services)
Types of Population census
De Facto & De Jure
Method of counting people in DeFacto enumeration
- In the locality during census time
Characters of DeFacto enumeration
- Simple & economic
Where is DeFacto enumeration Adopted?
Egypt & England
Method of counting in DeJure enumeration
According to actual residence
Characters of DeJure enumeration
More difficult, time consuming & expensive
Where is DeJure enumeration adopted?
USA
Methods of data collection in census
❶ Questionnaire filled by head of the family .
❷ Enumerators visit families collect data.
(Adopted in Egypt)
History of census in Egypt
- 1st: 1882 (total population was 6.7 million).
- Last: the 14th 2017 total population was 94.8 million.
- The central Agency for Public Mobilization &Statistics (CAPMAS) is responsible for census taking in Egypt.
Presentation of number of populations
1- Census population. The number of populations during census year.
2- Estimated population. The number is estimated at dates other than census years.
3- Mid-year population (Census or estimated): i.e. number of population at the middle of a given year (first of July).
Census population
The number of populations during census year
Estimated population
The number is estimated at dates other than census years.
Mid-year population
(census or estimated): i.e. number of population at the middle of a given year (first of July).
Methods of estimation of population
- Natural increase method
- Arithmetic method
- Geometric method
- Graph method
Methods of estimation of population
- Natural increase method
- (Births –deaths) every year is added to last census
population. - It is rough method &suitable for countries with no or limited migration.
Methods of estimation of population
- Arithmetic Mean
- It assumes that there is constant annual increase in population
e.g.,
- if we want to calculate the population in 2018, already we know the census of 2007 is 200,000 individuals, and the census of 2017 was 250,000 so the average
- increase every year (mean annual increase) = (250,000-200,000)/10 years=5000 person /year.
- The estimated population in 2018 =250,000+5000
- The estimated population in 2019 =250,000+10,000 and so on
Methods of estimation of population
- Geometric Method
- Most accurate, use last census and annual rate of population growth (calculated using special formula).
Methods of estimation of population
- Graph Method
- Plotting the successive census populations on a graph & joined by a straight line that can be extended over future years.
- It can be used to find out the inter-census population at a given year& expected population of future years (assuming that population growth rate will not change).
Def of Population pyramid
A graphical presentation of the age & sex composition of a population of an area or country at a point in time.
What affects the shape of Population pyramid?
births, deaths, migration
Describe Population pyramid
- It is Back-to-back histograms (age is a continuous variable), one showing numbers of males, the other shows the numbers of females.
- The bars: represent age bands of 5 year-interval