# Sampling Methods Flashcards

1
Q

Population

A

The whole group of items of interest

2
Q

Census

A

A survey of the whole population

3
Q

Sample

A

A subset of the whole population

4
Q

Sampling Unit

A

Each individual member of a population

5
Q

Sampling Frame

A

A named or numbered list of all the members of the population

6
Q

Random Sampling

A

A sampling method where every member of the population has an equal chance of being selected

7
Q

Non-random Sampling

A

A sampling method that is not random, some members of the population have more chance of being selected

8
Q

What are the different types of random sampling?

A
• Simple random
• Systematic sampling
• Stratified sampling
9
Q

What are the different types of non-random sampling?

A
• Quota sampling

- Opportunity sampling

10
Q

What are the advantages of simple random sampling?

A
• Bias free
• Easy and cheap
• Each member has an equal chance of being selected
11
Q

What are the disadvantages of simple random sampling?

A
• Sampling frame needed
• Not suitable for large population
• Time consuming and expensive for large population
• Missing values in data
12
Q

What are the advantages of systematic sampling?

A
• Simple and quick to use
• Unbiased and representative
• Good for large samples / populations
13
Q

What are the disadvantages of systematic sampling?

A
• Sampling frame needed
• Introduce bias if sampling frame not random
• Missing values in data
14
Q

What are the advantages of stratified sampling?

A
• Accurately reflects population structure
• Proportional representation of groups within population
• Random selection within each strata
15
Q

What are the disadvantages of stratified sampling?

A
• Sampling frame needed

- Population must be classified into clear strata

16
Q

What are the advantages of quota sampling?

A
• Sample is representative of population
• No sampling frame needed
• Quick, easy and inexpensive
17
Q

What are the disadvantages of quota sampling?

A
• Introduce bias
• Population must be divided into groups = costly
• Increase scope of study = increase groups = increase cost
• Non-responses aren’t recorded
18
Q

What are the advantages of opportunity sampling?

A
• Easy to carry out

- Inexpensive

19
Q

What are the disadvantages of opportunity sampling?

A
• Introduce bias

- Dependent on individual researcher