1.2 sampling

Question 1

simple random sampling

Answer 1

• 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)

Question 2

systematic sampling

Answer 2

-required elements are chosen at regular intervals from an ordered list

Question 3

stratified sampling

Answer 3

• the population is divided into mutually exclusive strata (eg males and females) and a random sample is taken

Question 4

advantages of simple random

Answer 4

• free of bias
• easy and cheap small sample
• equal chance of selection

Question 5

disadvantages of simple random

Answer 5

• sampling frame is needed

- not suitable for a large sample size

Question 6

advantages of systematic

Answer 6

• simple, quick

- suitable for large sample/population

Question 7

disadvantages of systematic

Answer 7

• sample frame needed

- bias if the sampling frame is not random

Question 8

advantages of stratified

Answer 8

• guarantees proportional representation of groups within population

Question 9

disadvantages of stratified

Answer 9

• population must be clearly classified into distinct strata