🪵Intro to Demographic Methods Unit 2 – Data Sources: Census, Vital Stats, Surveys
Demography studies human populations, focusing on their characteristics, dynamics, and structure. Key concepts include population composition, cohorts, and rates that measure demographic events. Understanding these fundamentals is crucial for analyzing population trends and their societal impacts.
Demographic data comes from various sources, each with unique strengths and limitations. Censuses provide comprehensive snapshots, vital statistics record life events, and surveys offer detailed insights. These sources, along with emerging big data, form the backbone of demographic research and policy-making.
Mixed-mode surveys combine multiple data collection methods to improve response rates and representativeness
Strengths and Limitations of Each Source
Census data provides comprehensive coverage and detailed geographic granularity
Allows for analysis of small population subgroups and local-level planning
Limited by the decennial frequency and the risk of undercounting hard-to-reach populations
Vital statistics offer continuous and timely data on fertility, mortality, and nuptiality
Captures rare events (maternal deaths) and provides cause-of-death information
Data quality depends on the completeness and accuracy of event registration
Sample surveys enable the collection of detailed and specialized information
Provides flexibility in questionnaire design and allows for in-depth exploration of topics
Subject to sampling and non-sampling errors, and limited generalizability to the entire population
Administrative records leverage existing data collected for non-statistical purposes
Cost-effective and can provide longitudinal information on individuals
Data quality and completeness may vary across sources and over time
Big data sources offer high volume, velocity, and variety of data
Enables real-time monitoring and analysis of population dynamics
Biases in digital access and usage limit representativeness and interpretability
Real-World Applications and Case Studies
Census data informs electoral redistricting, infrastructure planning, and resource allocation
The US Census Bureau's decennial census guides the apportionment of congressional seats and the distribution of federal funds
Vital statistics are used to monitor public health, evaluate interventions, and inform policy
The Maternal Mortality Surveillance System in the US relies on death certificates and linkage with other data sources to identify and investigate maternal deaths
Fertility surveys, such as the Demographic and Health Surveys (DHS), provide insights into reproductive health and family planning
DHS data has been used to assess the impact of contraceptive prevalence on fertility rates in sub-Saharan Africa
Labor force surveys, like the Current Population Survey (CPS) in the US, monitor employment, unemployment, and labor market dynamics
CPS data is used to calculate the official unemployment rate and track disparities by age, sex, and race/ethnicity
The WorldPop project combines census, survey, and geospatial data to produce high-resolution population distribution maps
These maps support disaster response, disease surveillance, and resource targeting in low- and middle-income countries
Mobile phone call detail records have been used to estimate population displacement and migration flows
Analysis of mobile phone data provided insights into the spatial distribution of population movements following the 2010 Haiti earthquake