1.2 Geographic Data

Types of Geographic Data

Geographers use quantitative data (numerical, statistical — like census counts or GDP) and qualitative data (descriptive, non-numerical — like interviews or field observations). Data can be primary (collected firsthand, e.g., fieldwork, surveys) or secondary (compiled by others, e.g., government reports). Combining both types gives a fuller picture of spatial patterns and human-environment relationships.

Geospatial Technologies

GIS (Geographic Information Systems) layers multiple data sets onto maps for spatial analysis. GPS (Global Positioning System) uses satellites to pinpoint exact locations. Remote sensing gathers data from satellites or aircraft without physical contact, useful for tracking land use, weather, and environmental change over large areas.

Census Data and Its Limits

The census is a count of population characteristics, conducted periodically (the U.S. does one every 10 years). It's valuable for tracking demographic trends but has limitations: undercounting marginalized groups, self-reported inaccuracies, and rapid changes between census years. Geographers must critically evaluate data sources for bias, scale, and reliability.

Key terms

Quantitative data

Numerical, statistical data (e.g., population counts, GDP figures).

Qualitative data

Descriptive, non-numerical data (e.g., interviews, field observations).

GIS

Geographic Information System — software that layers spatial data sets onto maps for analysis.

Remote sensing

Collecting data about Earth's surface from satellites or aircraft without direct contact.

Census limitation

Can undercount marginalized groups and quickly become outdated between collection periods.

Try an AP-style question

GIS is best described as…

1. layered digital mapping and analysis
2. a global positioning device
3. a paper atlas
4. satellite photography only