1.2 sampling Flashcards
1
Q
simple random sampling
A
- every member of the population has an equal chance of being selected
- representative of the population
- remove bias
- generating random numbers or lottery sampling (hat)
2
Q
systematic sampling
A
-required elements are chosen at regular intervals from an ordered list
3
Q
stratified sampling
A
- the population is divided into mutually exclusive strata (eg males and females) and a random sample is taken
4
Q
advantages of simple random
A
- free of bias
- easy and cheap small sample
- equal chance of selection
5
Q
disadvantages of simple random
A
- sampling frame is needed
- not suitable for a large sample size
6
Q
advantages of systematic
A
- simple, quick
- suitable for large sample/population
7
Q
disadvantages of systematic
A
- sample frame needed
- bias if the sampling frame is not random
8
Q
advantages of stratified
A
- guarantees proportional representation of groups within population
9
Q
disadvantages of stratified
A
- population must be clearly classified into distinct strata
