Sampling Flashcards
RIGHT LET THAT STATS KNOWLEDGE POP OFFFF. Starting off strong
What is a sample?
Good bloody q
According to the English Oxford dictionary
A small part or quantity intended to show what the whole is like
What is a population
Group of people from whom a sample is drawn from
We use a target population if we want to investigate specific individual differences
What is random sampling
Each participant has equal chance of selection
What are the advantages and disadvantages of random sampling
A
-unbiased
-quick, easy and cheap
D
-researcher may end up w biased sample if too small
-subgroups of target population may be selected = doesn’t guarantee representative sample
What is volunteer sampling
i VolUnTeEr. I VOLunTeer AS tRIbuTE
Researcher advertises the study and people who see advert may get in contact and volunteer, e.g. poster on newspaper
What are the advantages and disadvantages of volunteer sampling
A
-quick, convenient and ethical if leads to informed consent
-allows more in-depth analysis and accurate results
D
-sample is biased because the participants are likely to be more highly motivated (volunteer bias, participant variable)
What is opportunity sampling
Asking people who are available at that time to take part e.g. researcher may ask parents picking children up from school
What are the advantages and disadvantages of opportunity sampling
A
-easy and fastest method
because just ask participants you can find
-convenient
D
-biased because sample is drawn from a small part of population
-unlikely to be representative of whole target population
What is stratified sampling
Selecting people from every portion of your population in the same proportions
then let elishka explain how to calculate the strata cos it not mentioned in class but its a q that will get asked <3
also go to statistics sampling methods flashcards for more detailed info on each methoddd
What are the advantages and disadvantages of stratified sampling
A
-reflects proportions of people in certain strata (group)
-avoids bias as once the researcher has decided what number they have no control over who is being selected
D
-not completely objective because researcher may decide on how people are listed before the selection
-there is a small chance of a ‘freak’ sample (DAS OFFENSIVE) which would not be truly representative
-time-consuming because all potential participants need to be assessed and categorised
What is systematic sampling
Selecting every nth name from a list
again get elishka to explain this <3
What are advantages and disadvantages of stratified sampling
A
-more representative than an opportunity sample because there should be equal representation of subgroups
D
-time-consuming because all potential participants need to be assessed and categorised
What are advantages and disadvantages of systematic sampling
A
-more representative than an opportunity sample because there should be equal representation of subgroups
D
-Sampling frame needed
-Can introduce bias if sampling frame not random (e.g. selecting every 7th value in a list of consecutive dates)
-May be missing values in sample
