7.2: Sampling

Question 1

Sampling

Answer 1

Sampling is the selection of participants to represent a wider population

Question 2

Reducing it each time:

Population —> what —> what?

Answer 2

Population —> Target population —> Sample

Question 3

In psychological research studies, what is the population?

Answer 3

In psychological research studies, the population is a large group of people that the researcher is interested in studying

Question 4

In psychological research studies, the population is a large group of people that the researcher is interested in studying.
What is it usually?

Answer 4

The population is usually a very specific group of people

Question 5

In psychological research studies, the population is a large group of people that the researcher is interested in studying.
The population is usually a very specific group of people.
Example

Answer 5

For example, children with autumn under 6 years old

Question 6

In psychological research studies, the population is a large group of people that the researcher is interested in studying.
The population is usually a very specific group of people.
For example, children with autumn under 6 years old.
What is this called?

Answer 6

This is called the target population

Question 7

In psychological research studies, the population is a large group of people that the researcher is interested in studying.
The population is usually a very specific group of people.
For example, children with autumn under 6 years old.
This is called the target population.
Within the target population, what will the researcher do?

Answer 7

Within the target population, the researcher will take an even smaller group of people called the sample

Question 8

In psychological research studies, the population is a large group of people that the researcher is interested in studying.
The population is usually a very specific group of people.
For example, children with autumn under 6 years old.
This is called the target population.
Within the target population, the researcher will take an even smaller group of people called the sample.
Example

Answer 8

For example, 20 children with autumn under 6 years old

Question 9

When is a group of participants representative?

Answer 9

A group of participants is representative if selected from a larger population so that it closely matches the characteristics of the population as a whole

Question 10

A group of participants is representative if selected from a larger population so that it closely matches the characteristics of the population as a whole.
The sample is a fairly what reflection of the population from which the sample is drawn?

Answer 10

The sample is a fairly accurate reflection of the population from which the sample is drawn

Question 11

Generalisation

Answer 11

Generalisation is the extent to which the findings from a study can be broadly applied to the population

Question 12

Generalisation is the extent to which the findings from a study can be broadly applied to the population, so if the sample is representative, what?

Answer 12

Generalisation is the extent to which the findings from a study can be broadly applied to the population, so if the sample is representative, the more likely it is that we can achieve this

Question 13

Bias

Answer 13

Bias is when certain groups are over or under represented within the sample

Question 14

Bias is when certain groups are over or under represented within the sample.
Example

Answer 14

For example, too many women, men, ect

Question 15

Bias is when certain groups are over or under represented within the sample.
For example, too many women, men, ect.
What does this do?

Answer 15

This limits the extent to which generalisations can made to the population

Question 16

Why do researchers use sampling?

Answer 16

Researchers use sampling, because they don’t generally have the means to test whole populations

Question 17

Samples are selected using sampling techniques that aim to do what?

Answer 17

Samples are selected using sampling techniques that aim to produce a representative sample

Question 18

Random sampling

Answer 18

Random sampling is where each member of a population has an equal chance of being selected

Question 19

Random sampling is where each member of a population has an equal chance of being selected.
What is one way to achieve this?

Answer 19

One way to achieve this is the lottery method

Question 20

Random sampling is where each member of a population has an equal chance of being selected.
One way to achieve this is the lottery method - what happens?

Answer 20

One way to achieve this is the lottery method - all the members of the target population are:

1. Given a number
2. Placed in a hat or tombola

Question 21

Random sampling is where each member of a population has an equal chance of being selected.
One way to achieve this is the lottery method - all the members of the target population are given a number and placed in a hat or tombola.
What are also used to generate random lists?

Answer 21

Computer programs are also used to generate random lists

Question 22

Random sampling is where each member of a population has an equal chance of being selected.
One way to achieve this is the lottery method - all the members of the target population are given a number and placed in a hat or tombola.
Computer programs are also used to generate random lists.
What does this result in?

Answer 22

This results in a sample selected in an unbiased fashion

Question 23

Opportunity sampling

Answer 23

Opportunity sampling involves selecting participants who are:

1. Available
2. Willing to take part

Question 24

Opportunity sampling involves selecting participants who are available and willing to take part.
Example

Answer 24

For example, asking people in the street who are passing

Question 25

Opportunity sampling involves selecting participants who are available and willing to take part.
For example, asking people in the street who are passing.
What did Sears (1986) find?

Answer 25

Sears (1986) found that 75% of university research studies use undergraduates as participants, simply for the sake of convenience

Question 26

What is volunteer sampling also known as?

Answer 26

Volunteer sampling is also known as self-selected

Question 27

Volunteer (self-selected) sampling

Answer 27

Volunteer (self-selected) sampling involves people volunteering to participate

Question 28

Volunteer (self-selected) sampling involves people volunteering to participate.
They select themselves as participants, often by doing what?

Answer 28

They select themselves as participants, often by replying to adverts

Question 29

Systematic sampling

Answer 29

Systematic sampling is when participants are selected using a set pattern, as every nth person is taken from a list to create a sample

Question 30

Systematic sampling is when participants are selected using a set pattern, as every nth person is taken from a list to create a sample.
What does this involve?

Answer 30

This involves:

1. Calculating the size of the population
2. Then assessing what size the sample needs to be to work out what the sampling interval is

Question 31

Systematic sampling is when participants are selected using a set pattern, as every nth person is taken from a list to create a sample.
This involves calculating the size of the population and then assessing what size the sample needs to be to work out what the sampling interval is.
Example

Answer 31

For example, if a company has:
1. A workforce of 1,000 employees
2. A sample of 20 participants is required
,then 1,000 ÷ 20 = 50, so take every 50th name from the list of employees to form the sample

Question 32

Stratified sampling

Answer 32

Stratified sampling is when participants are selected according to their frequency in the target population

Question 33

Stratified sampling is when participants are selected according to their frequency in the target population.
What is a stratified sample?

Answer 33

A stratified sample is a small-scale reproduction of a population

Question 34

Stratified sampling is when participants are selected according to their frequency in the target population.
A stratified sample is a small-scale reproduction of a population.
What does it involve?

Answer 34

It involves:

1. Dividing a population into characteristics important for the research, for example by age, social class, ect
2. Then the population is randomly sampled within each stratum (category)

Question 35

Stratified sampling is when participants are selected according to their frequency in the target population.
A stratified sample is a small-scale reproduction of a population.
It involves dividing a population into characteristics important for the research, for example by age, social class, ect and then the population is randomly sampled within each stratum (category).
If 12% of the population is between 20 and 30 years old, then what?

Answer 35

If 12% of the population is between 20 and 30 years old, then 12% of the sample is randomly selected from that age sector