Week 7: Measuring Migration

Question 1

Why do we need migration data?

Answer 1

It’s an essential component of population change - If we want to estimate the size of the population now or in the future (project the population) we need to be able to estimate net migration.W

Question 2

Which factors does migration affect?

Answer 2

• Population size
• Population structure (migration is often age and sex specific – and also selective by other characteristics e.g. health, skills)
• Population distribution (international migrants often enter in major towns and cities)

Question 3

What is gross migration?

Answer 3

The sum of all migration between areas being considered.

Question 4

What is net migration?

Answer 4

The difference between migration flows in both directions - this is often what we attempt to measure as it determines the impact on population size.

Question 5

List two direct sources of migration data.

Answer 5

• Population registers
• Censuses

Question 6

List an indirect source of migration data.

Answer 6

Administrative data such as NHS patient registers and Higher Education Statistics Agency data.

Question 7

Write the formula for migration rate.

Answer 7

Migration rate = Number of people moving in period/
Population at risk of moving in period