Research Methods Y1 - Sampling

Question 1

What is the definition of “Population”?

Answer 1

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

Question 2

What is the definition of “Sample”?

Answer 2

A sample is 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 3

What are “Sampling techniques”?

Answer 3

Sampling techniques are the methods used to select people from the population.

Question 4

What is “Bias” in the context of sampling?

Answer 4

Bias occurs in the context of sampling, when certain groups may be over- or under-represented within the sample selected. For instance, there may be too many young people or too many people of one ethnic origin in a sample. This limits the extent to which generalisations can be made to the target population.

Question 5

What is “Generalisation”?

Answer 5

Generalisation is the extent to which findings and conclusions from a particular investigation can be broadly applied to the population. This is made possible if the sample of participants is representative of the population.

Question 6

What is a random sample in psychology?

Answer 6

A random sample is a sophisticated form of sampling in which all members of the target population have an equal chance of being selected.

Question 7

How is a random sample selected?

Answer 7

A complete list of all members of the target population is obtained.

Each name on the list is assigned a number.

The sample is generated through a random lottery method or picking numbers from a hat.

Question 8

What is one evaluation point on random sampling?

Answer 8

A random sample is free from researcher bias. The researcher has no influence over who is selected, preventing them from choosing people who might support their hypothesis.

Question 9

What is another evaluation point on random sampling?

Answer 9

It is difficult and time-consuming to conduct. A complete list of the target population may be extremely difficult to obtain.

Question 10

What is a systematic sample in psychology?

Answer 10

A systematic sample is one where every nth member of the target population is selected, for example, every 3rd house on a street or every 5th pupil of a school register.

Question 11

How is a systematic sample produced?

Answer 11

A sampling frame is produced, listing all people in the target population in a pre-determined order (e.g., alphabetical).

A sampling system is nominated (e.g., every 3rd, 6th, or 8th person).

The researcher works through the sampling frame until the sample is complete.

Question 12

What is one evaluation point on systematic sampling?

Answer 12

Systematic sampling avoids researcher bias. Once the system for selection has been established, the researcher has no influence over who is chosen.

Question 13

What is another evaluation point on systematic sampling?

Answer 13

This method is usually fairly representative. For example, it would be possible, but quite unlikely, to get an all-male sample through systematic sampling.

Question 14

What is a stratified sample in psychology?

Answer 14

A stratified sample is a sophisticated form of sampling in which the composition of the sample reflects the proportions of people in certain sub-groups (strata) within the target population or the wider population.

Question 15

How is a stratified sample carried out?

Answer 15

The researcher first identifies the different strata that make up the population.
The proportions needed for the sample to be representative are worked out.
Participants that make up each stratum are selected using random sampling.

Question 16

What is one evaluation point on stratified sampling?

Answer 16

Stratified sampling avoids researcher bias. Once the target population has been sub-divided into strata, the participants that make up the numbers are randomly selected and beyond the researcher’s influence.

Question 17

What is another evaluation point on stratified sampling?

Answer 17

Stratified sampling provides a representative sample because it is designed to accurately reflect the composition of the population. This means that generalisation of findings becomes possible.

Question 18

What is an opportunity sample in psychology?

Answer 18

An opportunity sample consists of selecting people who are willing and available, such as asking people on the street or in a nearby coffee shop.

Question 19

What is one evaluation point on opportunity sampling?

Answer 19

Opportunity sampling is convenient. This method saves a researcher a good deal of time and effort, and it is much less costly in terms of time and money than random sampling.

Question 20

What is a limitation of opportunity sampling?

Answer 20

The sample is unrepresentative of the target population as it is drawn from a very specific area, such as one street in one town, so findings cannot be generalised to the target population.

Question 21

What is a volunteer sample in psychology?

Answer 21

A volunteer sample involves participants selecting themselves to be part of the study. It is also referred to as self-selection.

Question 22

How is a volunteer sample collected?

Answer 22

A researcher may place an advert in a newspaper or on a noticeboard.

Alternatively, willing participants may simply raise their hand when the researcher asks.

Question 23

What is one evaluation point on volunteer sampling?

Answer 23

Volunteer sampling is easy. It requires minimal input from the researcher and is less time-consuming than other forms of sampling.

Question 24

What is a limitation of volunteer sampling?

Answer 24

Volunteer bias is a problem. Asking for volunteers may attract a certain ‘profile’ of person, such as one who is helpful, keen, and curious, which might then affect how far findings can be generalised.