Sampling Methods

Question 1

What is opportunity Sampling?

Answer 1

A sample containing anyone in the vicinity who is willing and available.

Pros:
-convenient
-less costly (time & money)

Cons:
-sample is unrepresentative (data cannot be generalised)
-researcher bias (researcher has complete control over selection of participants)

Question 2

What is random sampling?

Answer 2

A sample where all members of the target population have an equal chance of being selected.

Pros:
-potentially unbiased
-CV/EV should be equally divided-> enhancing internal validity

Cons:
-difficult and time consuming to conduct
-sample can still be unrepresentative
-participants may refuse

Question 3

What is stratified sampling?

Answer 3

It reflects the proportions of people in subgroups of the target population.

Pros:
-produces a representative sample

Cons:
-complete representation of the target population is not possible

Question 4

What is systematic sampling?

Answer 4

Every nth member of the target population is selected.

Pros:
-objective (researcher has no influence on who is chosen)

Cons:
-time consuming
-participants may refuse to take part (resulting in a volunteer sample)

Question 5

What is volunteer sampling?

Answer 5

A self-selected sample, often replying to an advert.

Pros:
-easy (minimal effort required)
-less time consuming

Cons:
-volunteer bias (attract curious volunteers aiming to please the researcher, effects the generalised findings)