SOC 10 - Sampling (MET)

Question 1

What is a target population?

Answer 1

The entire group of people the researcher is interested in i.e., the group about which the researcher wishes to draw conclusions

Question 2

What is a population?

Answer 2

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

Question 3

What is a sample?

Answer 3

• A group of people who take part in a research investigation
• The sample is drawn from a (target) population and is presumed to be representative of that population, i.e. it stands ‘fairly’ for the population being studied

Question 4

What is a sample frame?

Answer 4

• A list of every person in the target population, e.g., names and contact details
• A sampling frame is needed for some sampling methods e.g. systematic sampling and random sampling

Question 5

What is random sampling?

Answer 5

• A random sample is when all members of the target population have an equal chance of being selected
• A list of all members of the target must be obtained and each nane on the list is assigned a number
• The actual sample is selected through a lottery system

Question 6

What is systematic sampling?

Answer 6

• This is when a member of the target population is selected for the study at regular intervals (every nth member)
• A sampling frame is is produced which is organised by, for example, alphabetical order
• A sampling system is nominated (e.g. every 3rd, 5th, or 8th person etc)
• Selection may begin from a randomly determined start to reduce bias
• The researcher works through the sampling frame until the sample is complete

Question 7

What is stratified sampling?

Answer 7

• A stratified sample is when the composition of the sample reflects the proportions of people in certain subgroups (strata) within the target population or the wider population
• The researcher first identifies the different strata (subgroups) that make up the population
• The proportions needed for the sample to be representative is calculated
• The participants that make up each stratum is then selected using random sampling

Question 8

What is opportunity sampling?

Answer 8

• This is when researchers decide to select anyone who happens to be willing and available
• The researcher simply takes the chance to ask whoever is around at the time of their study e.g. like in the street

Question 9

What is volunteer sampling?

Answer 9

• This involves participants selecting themselves to be part of the sample, hence, it is also referred to as self-selection
• To select a volunteer sample, a researcher may place an advert in a newspaper or on a common room noticeboard
• Alternatively, willing participants may simply raise their hand when the researcher asks

Question 10

What are the strengths and weaknesses of random sampling?

Answer 10

Strengths:
- The sample is likely to be representative and potentially unbiased so it can be generalised to the target population

Weaknesses:
- Everyone in the target population has an equal opportunity of being selected
- It is difficult and time-consuming to conduct, as a complete list of the target population may be extremely difficult to obtain
- You may still end up with a sample that in unrepresentative e.g. all women are selected
- Selected participants may refuse/be unwilling to take part

Question 11

What are the strengths and weaknesses of systematic sampling?

Answer 11

Strengths:
- It is very objective, as once the system for selection has been established the researcher has no influence over who is chosen

Weaknesses:
- Selected participants may refuse/be unwilling to take part making the sample unrepresentative
- It is difficult and time-consuming to conduct, as a complete list of the target population may be extremely difficult to obtain

Question 12

What are the strengths and weaknesses of stratified sampling?

Answer 12

Strengths:
- Produces a representative sample because it is designed to accurately reflect the composition of the population (meaning generalisation of findings becomes more possible)

Weaknesses:
- Selected participants may refuse/be unwilling to take part
- It is difficult and time-consuming to get full details of the subgroups within the target population
- The identified strata cannot reflect all the ways that people are different, so complete representation of the target population is not possible

Question 13

What are the strengths and weaknesses of opportunity sampling?

Answer 13

Strengths:
- It is more convenient, as it is less costly in terms of time and money than random and stratified sampling
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Weaknesses:
- Selected participants may refuse/be unwilling to take part
- High chance of bias
- The sample is unrepresentative of the target population as it is drawn from a very specific area so findings cannot be generalised to the target population
- The researcher has complete control over the selection of participants and, for example, may avoid individuals they do not like the look of (researcher bias)

Question 14

What are the strengths and weaknesses of volunteer sampling?

Answer 14

Strengths:
- It is easy, as it requires minimal input from the researcher (participants come to them)
- It is less time-consuming than other forms of sampling
- The researcher ends up with participants who are more engaged, more so than someone who was stopped on the street

Weaknesses:
- Selected participants may refuse/be unwilling to take part
- Requesting volunteers may attract a certain ‘profile’ of people who are more curious and may be more likely to try to please the researcher, thus the sample is more likely to be bias (which might affect how far findings can be generalised)