Ever wondered how we get the lowdown on the incredible diversity of people living on our planet? It’s not magic, it’s data! In this blog, we’re diving into the three fascinating sources that spill the beans on population trends: Population Census, Registration of Vital Events, and Sample Surveys. Collecting the data from population is very important for the growth of a country. Learn about age, sex, population growth, poverty, education, income, death, birth, migration, etc are crucial for the development. Through understanding the pattern of the population, we can apply or modify new methods or technique. Through this blog we look into each sources and learn the technique, characteristics and properties.
Population Census
History of Population Census
- In India during the reign of Emperor Ashoka(270 BC- 230 BC) took the census.
- In 3rd century, Arthashastra of Kautilya dealed with population.
- A complete census at regular intervals were first made in New France and Acadie in 1665.
- A complete enumeration of population was done 16 times during 1665 – 1754
- First census of USA was taken in1754.
- First census of England was taken at 1801.
- During 1965 – 1974, a total of 185 countries conducted census.
Definition
A census of the population is the total process of collecting, compiling, evaluating, analyzing and publishing demographic, economic and social data pertaining at a specific time, to all the persons in the country or in a well de-limited part of a country.
Features
- Each individual is separately but only once enumerated.
- They record important characteristics of each person separately .
- It covers a precisely defined territory such as entire country or well defined part of it.
- Reference period is predetermined.
- It takes at regular intervals ( usually 10 years ).
- From 1881 onwards, census in India has been taken at regular interval ( 10 years).
- In USA, the interval is 5 years.
History of census in India
- First census occurred in 1881.
- The 1971 census was the 11th and marked the completion of 100 years of census taking in India.
- In 1972, the centenary of the Indian census was Celebrated.
- The census of 1951 was the first census conducted in Independent India.
- The report of the 1951 census discussed the growth and structure of the population of the population and its economic development.
- The 1981 was the international year of Disabled persons.
- De facto Census : Enumeration of individuals as of where they are found in the census, regardless of where they normally reside.
- De jure Census : numeration of individuals as of where they usually reside, regardless of where they are on census day.
Vital Statistics or Registration of Vital events
Vital Events
It refer to significant life occurrences that are essential to the demographic and statistical understanding of a population. They are Birth & Death, Still birth or foetal death, changes may takes place like marriage or divorced.
Vital Records
It refer to significant life occurrences that are essential to the demographic and statistical understanding of a population.
Vital Registration System
Birth, death, marriage and divorces are occurring continuously. Hence such events are continuously recorded. It is a government-led initiative designed to systematically and officially record and document vital events within a population.
Vital Statistics
The resulting events are compiled and the resulting statistics are vital statistics.
Civil Registration system
is a government-led mechanism for the continuous, permanent, and compulsory recording of vital events within a population. The primary objective of a civil registration system is to maintain accurate and comprehensive records of key life events, including births, deaths, marriages, and sometimes divorces. In 17th century, civil registration system was introduced in the colonies of Massachusetts Bay and New Plymouth.
Bengal Birth and Death Registration act (1873)
The Act mandated the compulsory registration of births and deaths throughout Bengal, laying the foundation for a more systematic and centralized vital registration system.
Births, Deaths, and Marriages Registration Act (1886)
This Act was one of the earliest attempts to establish a systematic system for registering births, deaths, and marriages in India. Initially, registration under the Act was voluntary for certain classes of people. However, over time, it became compulsory for most of the population.
Sample Surveys
A sample survey is a methodical approach that involves gathering data from a subset, or sample, of the entire population to draw inferences about the population itself. The goal is to extrapolate insights from the sample to make informed generalizations about the entire population. This process involves designing a questionnaire or interview protocol, selecting a representative sample, collecting responses, and analyzing the results.
Advantages of Sample Surveys
- Conducting a survey on an entire population can be time-consuming and expensive. Sample surveys provide a more cost-effective way to gather data while maintaining a high level of accuracy.
- Surveys allow researchers to efficiently collect a large amount of data from a relatively small sample.
- In situations where it is impractical to collect data from every individual in a population (due to size, time constraints, or logistical challenges), a well-designed sample survey becomes a practical alternative.
- By carefully selecting a representative sample, researchers can achieve a high degree of precision in their estimates.
- Sample surveys offer flexibility in terms of study design, allowing researchers to adapt their methods to different contexts, populations, and research questions.
Disadvantages of Sample Surveys
- One of the primary challenges is the potential for sampling bias. If the chosen sample does not accurately represent the characteristics of the entire population, It can lead to skewed results.
- While sample surveys provide valuable insights, there is always a risk that the findings may not perfectly generalize to the entire population
- The size of the sample is crucial. If the sample size is too small, the results may lack statistical significance.
- Sample surveys are subject to random variation and may not capture the true characteristics of the population accurately.
- The accuracy of a sample survey is highly dependent on the quality of the questionnaire. Poorly designed questions can lead to biased or unreliable responses.
Important Demographic Sample Surveys conducted in India
- National Sample Survey : by institute of politics and Economics, Poona ( 1952 – 1956 )
- The mysore Population Study (1953) : The Mysore Population Study holds a crucial place in India’s demographic history and beyond. The study was a collaborative effort between the United Nations and the Government of India
- The Patna Demographic Survey (1955) : It was a large-scale study was in the city of Patna, India, to collect data on the city’s population and demographics. Demographic Research Centre of the Patna University carried out the survey.
- The Family of Planning Survey (1970) : It was the first nationally representative family planning survey conducted in India. the Government of India’s Ministry of Health and Family Planning commissioned it.
The National Sample Survey
- the National Sample Survey Office (NSSO) conducts the National Sample Survey (NSS) in India.
- The primary objective of the NSS is to collect data through sample surveys to generate reliable and comprehensive socio-economic information for policy formulation, planning, and decision-making at both the national and state levels.
- First round of NSS was in 1950.
- Topics Covered : Fertility, Mortality, Population growth, economically active population, family planning, employment and unemployment, consumer’s expenditure patterns, housing conditions.
ORG Family Planning Survey
- This survey covered entire country except Jammu & Kasmir, NEFA & the offshore Island.
- Collected data from currently married women in reproductive age group.
- They collected data through face-to-face interviews conducted by trained personnel using a structured questionnaire.
Dual Report System
This involves collecting vital events, like births and deaths, through two independent methods simultaneously. This helps ensure accuracy and completeness of the data, especially in regions with limited resources or unreliable record-keeping. The two independent procedures are:
- The registration of Birth & Death.
- Sample Survey
Sample Registration System in India
- First SRS was in 1963-1964.
- They used technique of dual report system.
- The primary objective of the SRS is to provide reliable estimates of birth rates, death rates, and other vital indicators at the national and sub-national levels.
- Trained enumerators visit sampled households on a regular basis to collect information on births and deaths.
- The SRS covers the entire country, including rural and urban areas.
- The SRS data collection is continuous, and they release updates periodically.
International Publications
- Demographic Year Book – UN
- Statistical Year Book – UN
- Epidemiological & Vital Records – WHO
Types of Errors in Population Data
- Sampling Error
- Non Sampling Error
- Coverage Error
- Measurement Error
- Frame Error
- Processing Error
- Response Error
- Temporal Error
- Selection Bias
- Confounding Variance
For detailed study of history of population studies https://learnthrill.com/development-of-population-studies-in-india/
References : Principle of Population Studies by Asha Bhende, Demographic Techniques
