Sampling

Question 1

What is opportunity sampling?

Answer 1

Participants happen to be available at the time of the study

Question 2

Strengths of opportunity sampling

Answer 2

• Time saving
• Less costly

Question 3

Limitations of opportunity sampling

Answer 3

• Not representative of the whole population
• Researcher bias

Question 4

What is random sampling?

Answer 4

All members of the population have equal chance of being selected

Question 5

What is systematic sampling?

Answer 5

Predetermined system where every nth member is selected

Question 6

What is stratified sampling?

Answer 6

Identify strata (subgroup) and then take random sample from each strata

Question 7

What is volunteer sampling?

Answer 7

Involves self selection where participant offers to take part

Question 8

Strengths of random sampling

Answer 8

• No researcher bias

Question 9

Limitations of random sampling

Answer 9

• Time consuming
• Volunteer bias (can refuse participation)

Question 10

Strengths of systematic sampling

Answer 10

• Avoids researcher bias
• Usually fairly representative

Question 11

Limitations of systematic sampling

Answer 11

• Not truly unbiased unless you use a generator and then use systematic

Question 12

Strengths of stratified sampling

Answer 12

• No researcher bias
• Produces representative data

Question 13

Strengths of volunteer sampling

Answer 13

• Not time consuming as quick access to willing participants

Question 13

Limitations of stratified sampling

Answer 13

• Time consuming to identify strata and then contact people
• Cannot have complete representation

Question 14

Limitations of volunteer sampling

Answer 14

• Volunteer bias as they may attract a particular profile which may affect generalisation