Social Science Migration Patterns and Processes

A comprehensive vocabulary flashcard set covering 140 key migration terms, demographic measures, theories, figures, legal definitions, and statistics from the Social Science Resource Guide.

International migrant population (2024)

Estimated at 304 million people worldwide by the United Nations, representing approximately 3.7 percent of the global population.

Age of Migration

A characterization applied by Stephen Castles and Mark J. Miller to describe the period since the late twentieth century due to the unprecedented scale of global migration.

Stephen Castles and Mark J. Miller

The scholars who characterized the period since the late twentieth century as an 'Age of Migration'.

Voting with feet

An expression describing how migrants relocate to resolve labor market mismatches or realize residential preferences in urban, suburban, or rural settings.

Labor market mismatch

A situation where available jobs and people looking for jobs are located in different places, prompting migration.

Spatial mobility

A broad concept encompassing all forms of geographic movement by humans, including commuting, vacation travel, and relocations.

Social mobility

The movement of individuals or groups up and down a social hierarchy, reflecting a change in social status.

Migration

The movement of a person between two places for a certain period of time, involving both a spatial and a temporal dimension.

Activity space

The geographic area where an individual works, shops, and socializes on a daily basis, which generally changes when a person migrates.

Spatial dimension of migration

The aspect of migration defined by movement across political boundaries, such as a county, state/province, or country.

Temporal dimension of migration

The timeframe over which a move takes place, requiring a degree of permanence to distinguish migration from short-term trips.

Address-based migration measurement interval

An approach in censuses and surveys (such as the ACS and CPS) that identifies moves by comparing current residence to where a person lived 1 or 5 years ago, or at birth.

Impact of Covid-19 pandemic on county migration

Between 2020 and 2021, counties under 30,000 gained population through net domestic migration, while counties over 1 million experienced significantly increased outmigration.

Migrant (mover)

A person who migrates or changes their place of residence.

Non-migrant (stayer)

A person who does not move or change their place of residence.

Origin

The current or initial place of residence from which a migrant moves.

Destination

The target location or new place of residence to which a migrant moves.

Out-migration

The movement of people away from a specific location.

In-migration

The movement of people into a specific location.

Immigration

In-migration that occurs across national boundaries.

Emigration

Out-migration that occurs across national boundaries.

In-migration and out-migration correlation

The phenomenon where places with high levels of in-migration also tend to experience high out-migration due to constant turnover, high living costs, and job competition.

Net migration

The numerical difference between the number of in-migrants and out-migrants for a specific location.

Positive net migration

A state where in-migration exceeds out-migration, resulting in a net population gain from migration.

Negative net migration

A state where out-migration exceeds in-migration, resulting in a net population loss from migration.

Natural increase

The balance between births and deaths in a population, which acts alongside net migration to determine total population changes.

Migration stream

A body of migrants moving from a specific origin to a common destination during a given time period.

Counterstream

A smaller flow of migrants moving in the opposite direction of a primary migration stream.

New York to Florida migration stream (2023)

A migration stream where 71,138 New Yorkers moved to Florida while a counterstream of 24,749 Floridians moved to New York.

Directional bias

The tendency for migration flows to be concentrated in specific directions rather than evenly or randomly distributed.

Voluntary migration

Moves made freely by choice as migrants seek educational, economic, or lifestyle opportunities.

Involuntary (forced) migration

Moves compelled by external circumstances beyond a migrant's control, such as conflicts, persecution, or disasters.

Reluctant migration

Moves where individuals relocate because local adverse conditions compel them to move, even if they would prefer to remain.

Long-distance moves

Relocations undertaken predominantly for economic reasons, such as accepting a new job.

Short-distance moves

Relocations undertaken primarily for lifestyle reasons, such as obtaining a larger home.

Temporary migration

Movement where the migrant intends to stay at the destination for a limited duration before returning home.

Permanent migration

Movement where the migrant intends to stay at the destination indefinitely with no plan to return.

Onward migration

A subsequent migration move made to a new destination after a previous move.

Return migration

A move where a migrant goes back to their previous place of residence or origin.

International migration

Migration that involves crossing sovereign national boundaries.

Internal migration

Migration occurring within the subnational borders of a single country.

Interregional migration

Movement between distinct geographic regions within the same country.

Inter-state migration

Movement from one state or province to another within the same national territory.

Urbanization

The migration of people from rural areas into urban cities.

Counterurbanization

The movement of people away from urban cities into rural areas.

Intraurban mobility

Residential relocation within the boundaries of a single city or metropolitan area.

Transnational migration

A process where international migrants maintain active, durable social, economic, and political links to their country of origin.

Cost-benefit migration evaluation

A deliberative decision-making process in which prospective migrants evaluate tangible and intangible costs against expected benefits before moving.

Stepwise migration

A strategy where a migrant reaches a long-distance destination through a series of smaller, incremental moves.

Migrant capital

The savings, job skills, and social networks accumulated by a migrant during intermediate steps of migration.

Chain migration

A migration process where pioneer migrants pass information and assistance to relatives and friends, encouraging them to follow to the same destination.

Zhejiang Villages

Migrant enclaves formed in Beijing by rural-urban migrants from Zhejiang province through chain migration.

Ethnic neighborhoods

Distinct urban enclaves (such as Chinatowns and Little Italies) formed in part through chain migration.

Family unification policy

A long-standing U.S. immigration framework allowing citizens and permanent residents to sponsor close family members from abroad.

Green card

An official USCIS identity document proving that a person is a lawful permanent resident of the United States.

Repeat migration

Recurring migration behavior, estimated to represent over sixty percent of all migration events.

Halfbacks

Retirees who initially move to Florida but later relocate partway back north to states such as Georgia or North Carolina.

Seasonal migration

Periodic movement driven by seasonal fluctuations in weather or labor availability, such as agricultural harvesting.

Snowbirds

Retirees or remote workers from Northern regions who winter in warmer Southern locations (e.g., Florida, Arizona, Texas) and return north for summer.

Ernst Georg Ravenstein

A German-English geographer and cartographer (1834–1913) who analyzed European and North American census data to formulate eleven 'laws of migration'.

Victoria Medal

The inaugural award presented to Ernst Georg Ravenstein by the Royal Geographical Society in 1902 for cartographic contributions.

Ravenstein's First Law of Migration

The principle stating that most migrants move only a short distance.

Ravenstein's Second Law of Migration

The rule stating that migration proceeds geographically in a step-by-step fashion.

Ravenstein's Third Law of Migration

The principle that long-distance migrants generally move to major centers of commerce and industry.

Ravenstein's Fourth Law of Migration

The rule stating that each main stream of migration produces a compensating counterstream.

Ravenstein's Fifth Law of Migration

The law stating urban dwellers are less migratory than rural people—a premise determined invalid by modern reappraisals.

Ravenstein's Sixth Law of Migration

The observation that women move more within their birth country, but men venture beyond national borders more frequently.

Ravenstein's Seventh Law of Migration

The rule stating that most migrants are adults and families seldom move out of their country of birth.

Ravenstein's Eighth Law of Migration

The rule positing that large towns grow more by migration than by natural population increase.

Ravenstein's Ninth Law of Migration

The principle stating that migration volume increases with commercial/industrial growth and transportation improvements.

Ravenstein's Tenth Law of Migration

The law asserting that the primary direction of migration is from agricultural regions to commercial/industrial centers.

Ravenstein's Eleventh Law of Migration

The rule stating that economic factors constitute the primary cause of migration.

Migration age profile

The empirical pattern showing migration propensity peaking among young adults (~25 years) and declining with age before a minor retirement peak.

Demographically dense years

Young adult life stages characterized by a dense concentration of life course transitions (e.g., college, first job, marriage).

Migration selectivity

The phenomenon where migrants systematically differ in age, education, skills, and risk tolerance compared to non-migrants.

Brain drain

The net loss of educated, skilled, and highly productive residents from an origin region through out-migration.

Brain gain

The net influx of educated, skilled, and highly productive individuals into a destination region through in-migration.

Persian Gulf labor migration selectivity

A labor flow dominated by young and middle-aged South Asian men performing physically demanding work in construction and industry.

Philippine labor migration selectivity

A labor stream to South and East Asia composed predominantly of female migrants working as domestic helpers.

Sun Belt

A U.S. region spanning Florida, Texas, and Arizona that selectively draws large numbers of retiree migrants.

Demographic transition model

A framework describing how a country's birth and death rates shift from high to low levels as it industrializes.

Wilbur Zelinsky

A Pennsylvania State University geographer who proposed the Mobility Transition Model in 1971.

Mobility transition model

A theory linking five stages of migration behavior to corresponding stages in demographic development.

Stage 1 Mobility Transition (Premodern traditional societies)

A mobility phase with minimal migration, limited mainly to short local moves between neighboring villages.

Stage 2 Mobility Transition (Early transitional societies)

The most mobile phase, marked by high rural-urban migration, frontier moves, emigration, and rising circulation.

Stage 3 Mobility Transition (Late transitional societies)

A phase where rural-urban migration, frontier moves, and emigration decline while circulation continues to rise.

Stage 4 Mobility Transition (Advanced societies)

A phase with high inter- and intra-urban mobility, sustained high circulation, and low rural-urban migration.

Stage 5 Mobility Transition (Superadvanced society)

A hypothesized future stage where residential moves drop due to telecommunications, while urban-urban moves and low-skilled immigration persist.

Circulation

Short-term, repetitive, or cyclical geographic movements occurring on a regular basis without permanent change of residence.

Monetary costs of migration

Direct financial outlays required for traveling, packing, securing housing, and job hunting in a new place.

Psychic costs of migration

Intangible emotional stress resulting from separating from family, friends, and familiar surroundings.

Current Population Survey (CPS ASEC)

An annual March U.S. Census Bureau survey tracking 20 specific migration reasons categorized into family, employment, housing, and other reasons.

Housing-related move reasons

The largest overall category of U.S. moves in CPS data, accounting for 49.7 percent in 2000 and 41.3 percent in 2023.

Shift in U.S. movers (2000 to 2023)

A significant decline in total annual U.S. movers from 43.4 million in 2000 down to 25.6 million in 2023.

Macro (aggregate) migration approach

A theoretical approach analyzing spatial migration streams, population flows, and structural economic drivers.

Micro (behavioral) migration approach

A theoretical approach examining how individual or household decision-making processes lead to migration.

Macroadjustment theory

A neoclassical theory viewing interregional wage differences as the primary driver moving labor to achieve spatial equilibrium.

Labor market equilibrium

A theoretical outcome where labor flows systematically equalize wage rates and eliminate spatial wage gaps.

Disequilibrium perspective on migration

The empirical finding that migration often reinforces existing regional disparities in wages and unemployment rather than eliminating them.

Human capital model of migration

An economic framework treating migration as an investment based on prospective net lifetime earnings minus costs.