Sampling

Question 1

What is meant by the term population?

Answer 1

A group of people who are the focus of the researcher’s interest, from which a smaller sample is drawn.

Question 2

Why is it usually not possible to include all members of the population in a study?

Answer 2

Due to practical and economic factors such as time and money.

Question 3

What is a sampling technique?

Answer 3

A method used to select participants from the population.

Question 4

What is meant by the term generalisation?

Answer 4

The extent to which findings and conclusions from a particular investigation can be broadly applied to the population.

Question 5

What is random sampling?

Answer 5

All members of the population have an equal chance of being chosen.
- All population members are numbered then through a lottery method, a sample of random numbers is chosen (which correspond to members of the population).

Question 6

What is the target-population?

Answer 6

A subset of the general population that is more specific.

Question 7

Random sampling makes use of lottery methods, what are these?

Answer 7

A computer-based randomise or picking numbers from a hat.

Question 8

In which sample does every member of the population have an equal opportunity for being selected?

Answer 8

Random sampling.

Question 9

What is meant by the term sample?

Answer 9

The group of people selected who take part in the research, they are drawn from the (target) population and is presumed to be representative of the whole population.

Question 10

The vast majority of samples contain some type of bias, what is meant by the term bias?

Answer 10

When certain groups may be over or under-represented in the sample.

Question 11

Why do we assume that the sample is representative of the target population?

Answer 11

So that we can generalise our results to a wider audience.

Question 12

Why does bias in the sample limit the ability to generalise results?

Answer 12

Because when there is bias in the sample, it is no longer representative of the population and cannot be generalised.

Question 13

From where is a sample taken?

Answer 13

From the (target) population.

Question 14

Explain the process of taking a random sample:

Answer 14

1) A complete list of all target population members is acquired.
2) Every member is numbered.
3) The sample of numbers is generated through some lottery method.
(Each number corresponds to a member of the pop.)

Question 15

List the main sampling techniques used to generate a sample from a population:

Answer 15

• Random sampling,
• Systematic sampling,
• Stratified sampling,
• Opportunity sampling,
• Volunteer sampling.

Question 16

Which sampling type uses the mathematical ‘nth’ term sequence?

Answer 16

Systematic sampling.

Question 17

What makes generalisation possible?

Answer 17

Generalisation is made possible by the sample being representative of the population.

Question 18

How do you generate a sampling frame for systematic sampling?

Answer 18

Make a list of every member of the target population ordered by some factor, e.g. alphabetically.

Question 19

What is an opportunity sample?

Answer 19

Where the researcher simply takes anyone who is available and accessible at the time.

Question 20

Which type of sampling technique would generate a mathematical sequence?

Answer 20

Systematic sampling.

Question 21

Which technique has been referred to as a ‘self-selection’ process?

Answer 21

Volunteer sampling.

Question 22

Explain how a researcher may carry out a volunteer sample?

Answer 22

They may place an advert in a newspaper or a poster and wait for participants to come forwards.

Question 23

Which sampling technique may involve walking into the street and taking anyone who is down to do the study?

Answer 23

Opportunity.

Question 24

A sampling frame is required for which type of sampling?

Answer 24

Systematic.

Question 25

Which sampling method is the only one which the researcher doesn’t “select” participants themselves?

Answer 25

Volunteer sample.

Question 26

Which forms of sampling are considered the most sophisticated?

Answer 26

Random sampling and Stratified sampling.

Question 27

What is the aim of stratified sampling?

Answer 27

To obtain a sample in which the sample reflects the proportions of people in certain sub-groups (stratas) within the (target) population.

Question 28

What can be done to a systematic sample to try and increase the randomness?

Answer 28

The sampling system (‘nth number’) can be decided through a random number generator.

Question 29

Which sampling technique may involve waiting outside a supermarket and stopping every 10th person who comes in?

Answer 29

Systematic sample.

Question 30

Explain how to carry out a systematic sample:

Answer 30

• Create a sampling frame by organising every member of the target population into a list.
• Nominate a sampling system (e.g. every 8th person).
• Work through the sampling frame until sample is complete.

Question 31

What are stratas?

Answer 31

They are sub-groups of a wider population used in stratified sampling.

Question 32

AO3 - Advantages of volunteer sampling.

Answer 32

• Requires little effort from the researcher and easy to get a sample.

Question 33

Which sampling technique involves generating a strata?

Answer 33

Stratified sampling.

Question 34

AO3 - Advantages of random sampling.

Answer 34

• Unbiased because every member of the population has an equal chance of being chosen.

Question 35

AO3 - Disadvantages of random sampling.

Answer 35

• Can be very time-consuming to number and generate is target population is large.
• Sample may still be unrepresentative due to the random nature.

Question 36

AO3 - Disadvantages of volunteer sampling.

Answer 36

• Tends to attract a certain type of person (people-pleasers).

Question 37

AO3 - Advantages of opportunity sampling.

Answer 37

• Very easy and accessible to gain participants.

Question 38

AO3 - Disadvantages of opportunity sampling.

Answer 38

• Not representative as only specific places or areas.

Question 39

AO3 - Advantages of systematic sampling.

Answer 39

• Avoids any forms of researcher bias.

Question 40

AO3 - Disadvantages of systematic sampling.

Answer 40

• Can easily be unrepresentative of the population.

Question 41

AO3 - Advantages of stratified sampling.

Answer 41

• Highly representative of the population.

Question 42

AO3 - Advantages of stratified sampling.

Answer 42

• Highly representative of the population.

- Also no researcher bias as ptps are randomly selected.

Question 43

AO3 - Disadvantage for all sampling techniques.

Answer 43

Selected participants may also refuse to take part, which means it turn more into a volunteer sample.

Question 44

A disadvantage of volunteer sampling is that it may attract a certain type of person, what type of person is this?

Answer 44

Someone who is helpful, keen and curious.