Sampling Methods Flashcards
(15 cards)
Random Sampling
All members of the target population have equal chance of being chosen
- e.g. randomised numbers
Systematic Sampling
The nth member of the target population is selected
Sampling frame - list of people in the population
Stratified Sampling
In which the composition of the sample reflects the proportions of people in certain subgroups (strata) within the target population
- e.g. target population have 100 cyclists and 50 walkers, sample size will have 10 cyclists and 5 walkers
Opportunity Sampling
Selecting anyone who happens to be willing and available
- asking on the street etc
Volunteer Sampling
Involves participants selecting themselves to be part of the sample
Strengths of Random Sampling
Potentially unbiased
- increases internal validity
Strengths of Systematic Sampling
Objective
- researcher has no influence on who gets chosen once the sampling system is determined
Strengths of Stratified Sampling
Produces representative sample
- increased generalisability of data collected
Strengths of Opportunity Sampling
Convenient and less costly
Strengths of Volunteer Sampling
Simple
Less time-consuming
Researcher ends up with more-engaged participants
Limitations of Random Sampling
Difficult and time-consuming to conduct
Might end up with a sample that is unrepresentative
Limitations of Systematic Sampling
Time consuming
May not end up with a representative sample
Limitations of Stratified Sampling
Complete representation is not always possible
Limitations of Opportunity Sampling
Suffers from bias
- researcher has complete control over selection of participants
Unrepresentative of target population
- drawn from specific areas
Limitations of Volunteer Sampling
