Sampling Types

Question 1

What is random sampling

Answer 1

one where every combination (of a given size) of members of a given population has an equal likelihood being chosen as the sample.

Question 2

What is systematic sampling

Answer 2

When all members of the population are put into some order (unrelated to what you’re testing), and you systematically pick a bunch of them e.g. every third member.

Question 3

What is stratified sampling?

Answer 3

When you ensure each ‘strata’ is equally represented in your survey/test by scaling the numbers and proportions to the same as the one with the greatest number in it

Strata being different groups within the population e.g. men and women, different age groups, etc

Question 4

What is cluster sampling?

Answer 4

When the population is broken up into groups/clusters, each of which are representative of the total population.

You pick one of these clusters and do your test on them

Question 5

What is convenience/opportunity sampling?

Answer 5

You just ask/survey people whom the opportunity presents itself to

e.g. if you were walking around a street you’d ask people walking past

Question 6

What is volunteer sampling?

Answer 6

Speaks for itself really, people volunteer to take part in it