Sampling Techniques Flashcards
What is the definition for Random sampling
All members of the public have equal chance of being selected, picked through a lottery method.
What is the definition for Stratified Sampling
Where the composition of the sample reflets the proportions of people in certain subgroups
What is the definition for Systematic Sampling
Every nth member of the target population is selected (every third house on the street)
What is the definition for Opportunity Sampling
Select anyone who is willing to participate in the test (like on the street)
What is the definition for Volunteer Sampling
Participants selecting themselves to be apart of the test
What are the strengths for random sampling
Free from Researcher bias
What are the strengths for Stratified sampling
Avoids researcher bias,
Investigator cannot influence choices after strata’s have been
decided
Representative sample
What are the strengths for systematic sampling
Avoids researcher bias
Fairly representative
What are the strengths for opportunity sampling
Saves time and effort and much less costly
What are the strengths for volunteer sampling
Minimal input as participants come to you
What are the drawbacks for random sampling
Difficult and time consuming
Could still be unrepresentative
Some participants may refuse to take part
What are the drawbacks for stratified sampling
Some participants may refuse to take part
Selected strata’s cannot reflect all people of the sub-group
What are the drawbacks for systematic sampling
Some participants may refuse to take part
What are the drawbacks for opportunity sampling
Some participants may refuse to take part
Sample is representative as it only uses people from ‘one street’
Researcher has control over who is picked
What are the drawbacks for volunteer sampling
Volunteer bias (volunteering participants may be of similar character)
