Sampling Methods Flashcards
sampling - sample
selecting units from a population to study to generalise results
sampling - representative sample
contains relevant characteristics of survey population to be able to generalise to them
sampling - representativeness is affected by:
- sample size (larger=more representative)
- sampling frame: list of those in survey population (must be complete)
- sampling method (techniques used to select individuals must be generalisable and accurate to whole survey population
sampling - random sampling
every individual in survey population has equal chance of being selected
subject to laws of chance - unrepresentative
sampling - systematic sampling
individuals selected from sampling frame at regular intervals
unrepresentative - due to chance
sampling - stratified random sampling
sampling fram subdivided into small sampling frames then individuals selected at random
sampling - quota sampling
interviewers select people that fit into categories
interviewer may be bias
sampling - snowball sampling
people w/characteristics relevant offer other people willing to cooperate in research until sample gradually builds up
useful when no sampling frame
not random/representative as sample is self-selecting (bias)