Research Methords : Sampling

Question 1

Definition of population

Answer 1

Refers to a large group of individuals that a particular researcher is interested in studying

Question 2

Definition of target population

Answer 2

Subset of the general population

Question 3

Why does the sample need to be representative of the target population

Answer 3

So that generalisation of findings becomes possible

Question 4

Why is it difficult to represent populations in any given sample

Answer 4

Du to the inevitability diverse nature of populations of people

Question 5

What do the vas majority of samples contain

Answer 5

A degree of bias

Question 6

Definition of sampling technique

Answer 6

The method used to select people from the population
Aims to produce a representative sample

Question 7

What is a RANDOM SAMPLE

Answer 7

All members of the target population have an equal chance of being selected

Question 8

How do you carry out random sampling

Answer 8

Obtain a complete list of all members of the target population
All of the names on the list are assigned a number
Actual sample is selected through the use of some lottery method
Eg. Names out of a hat

Question 9

What is systematic sampling

Answer 9

Every nth member of the target population is selected

Question 10

What is produced from a systematic sample

Answer 10

A sampling frame

Question 11

What is a sampling frame

Answer 11

A list of people in the target population organised into categories
For instance alphabetical order

Question 12

How does systematic sampling start off

Answer 12

May begin with a randomly determined start to reduce bias - to get n
The researcher then worked through the sampling frame until the sample is complete

Question 13

What is a stratified sample

Answer 13

Sophisticated - like random
The composition of the sample reflects the proportions of subgroups (strata) within the target population organised into wider population

Question 14

How to carry out strata

Answer 14

Identify different strata that make up the population
Proportions needed for the sample to be representative are worked out
The participants make up each stratum are selected using random sampling

Question 15

What is opportunity sampling

Answer 15

The researcher takes the chance to ask whoever is around at the time of the study
Decides to select who is willing and available

Question 16

Why may researchers use opportunity sampling

Answer 16

Representative samples of target population are so difficult to obtain

Question 17

What is a volunteer sample

Answer 17

Involves participants selecting themselves to be part of the sample

Question 18

How may a researcher carry out a voulenteer sample

Answer 18

Advertisements so in a newspaper or on a common room noticeboard
Willing participants may raise their hand when the researcher asks

Question 19

Strength of random sampling

Answer 19

Potentially unbiased
Confounding and extraneous variables should be equally divided between groups
Increases internal validity

Question 20

Limitation of random sampling

Answer 20

Difficult and time consuming to conduct
A complete list of the target population may be extremely difficult to obtain

Question 21

Limitation of random sampling

Answer 21

End up with a sample that is still unrepresentative
The laws of probability suggest that random sampling is likely to produce a more representative sample than opportunity sampling however random sampling may select for example 20 female psychology teachers from Stratford called Chloe

Question 22

Limitation for all sampling

Answer 22

Selected participants may refuse to take part which means you end up with something like a volunteer sample

Question 23

Strength of systematic sampling

Answer 23

Objective
Onc3 the system for selection has been established the researcher has no influence over who is chosen

Question 24

Limitation of systematic sampling

Answer 24

Time consuming and in the end participants may refuse to take part so end up with volunteer sample

Question 25

Strength of stratified sampling

Answer 25

Produces representative sample Designed to accurately reflect composition of population Generalisation of findings is possible

Question 26

Limitation of stratified

Answer 26

Identified strata cannot reflect all the ways that people are different Complete representation of target population is not possible

Question 27

Strength of opportunity sampling

Answer 27

Convenient Much less costly in terms of time and money List of members of target population is NOT required like in random sampling

Question 28

Limitation of opportunity

Answer 28

Suffer from two forms of bias Sample is unrepresentative of target population as it is drawn to a very specific area such as one street in one town so findings CANNOT be generalised to target population

Question 29

Limitation of opportunity

Answer 29

Researcher has complete control of the selection of participants May avoid people they do not like the look of Researcher bias

Question 30

Strength of voulenteer

Answer 30

Easy Requires minimal input from researcher and so is less time consuming Participants are more engaged as they chose to be apart of the study

Question 31

Limitation of volunteer

Answer 31

Volunteer bias May only attract a certain profile of a person Affects how far findings can be generalised