30 Required Models & Theories for AP Human Geography (copy)

Central Place Theory (Christaller)

Explains how settlements space out to provide goods/services.

Rank-Size Rule

City sizes follow a predictable rank pattern.

Primate City Rule

One city dominates, often more than twice the size of the second city.

Concentric Zone Model (Burgess)

Describes land use in U.S. industrial cities in rings.

Sector Model (Hoyt)

Explains land use in wedges along transport routes.

Multiple Nuclei Model (Harris–Ullman)

Cities develop multiple centers or nodes.

Latin American City Model (Griffin–Ford)

Features an elite spine with a CBD and peripheral squatter areas.

Southeast Asian City Model (McGee)

A mix of colonial CBD, port zone, and ethnic zones.

Bid-Rent Theory (Alonso)

Land value decreases with distance from the center.

Demographic Transition Model (DTM)

Describes how birth and death rates change with development.

Epidemiological Transition Model (ETM)

Analyzes how causes of death shift as development occurs.

Malthusian Theory

Suggests population growth outpaces food production, leading to checks.

Boserup Thesis

Claims population pressure drives agricultural intensification.

Population Pyramid + Dependency Ratio

Describes age/sex structure and economic burden.

Push–Pull Migration Model (Lee)

Migration influenced by push and pull factors with obstacles.

Ravenstein’s Laws of Migration

Describes common patterns in migration flows.

Zelinsky Mobility Transition Model

Migration patterns change according to development stage.

Gravity Model

Interaction between two places increases with size and decreases with distance.

Distance Decay / Friction of Distance

Effects weaken as distance increases.

Environmental Determinism vs Possibilism

Contrasts the idea that the environment controls versus humans adapt.

Sequent Occupance

Explains how places have layered cultural landscapes over time.

Hägerstrand Innovation Diffusion (S-curve)

Describes how innovations diffuse over time in a slow to rapid pattern.

Language Diffusion Models (Tree vs Wave)

Tree model = divergence; Wave model = spread through contact.

Geopolitical Theories: Heartland vs Rimland

Power dynamics based on geographic control of land.

Shatterbelt Theory

Describes regions prone to conflict between stronger powers.

von Thünen Model

Agricultural land use based on distance from a market.

Weber Least-Cost Theory

Industry locates to minimize transport and labor costs.

Rostow Stages of Economic Growth

Describes linear stages of development from traditional to mass consumption.

Wallerstein World-Systems Theory

Analyzes the relationship between core, periphery, and semiperiphery.

Clark–Fisher Sector Model

Describes the shift in economies from primary to secondary to tertiary sectors.