Types of Sampling

Question 1

Simple Random Sampling

Answer 1

Each member of the sample frame has an equal chance of being selected

Question 2

Opportunity Sampling

Answer 2

Members of the sample frame are selected based on things such as availability or convenience

Question 3

Systematic Sampling

Answer 3

Choosing members of the sample frame at regular intervals.

eg every tenth person

Question 4

Stratified Sampling

Answer 4

Spitting the sample frame into groups based on factors relevant to the research. Then taking a random sample of each roup in proportion to the size of that group.
Eg if 20% of fish are green, 20% of the data set will be from green fish

Question 5

Quota Sampling

Answer 5

Splitting the sample frame into groups based on research relevant factors. Then sampling based on things such as availability or convenience.

Question 6

Cluster Sampling

Answer 6

Splitting the sample frame into groups based on convenience. Then doing random sampling within the groups.

Question 7

What are Advantages and Disadvantages of Random sampling?

Answer 7

Ad:
Produces and unbiased sample
Dis:
Hard to eliminate sub-consious bias
Expensive
Time consuming
Requires a large part of population.

Question 8

What are Advantages and Disadvantages of Systematic sampling?

Answer 8

Ad:
Removes unwanted clustering of data
Easier than random to perform.
Dis:
Less random than random.
Reuires a large aount of the population

Question 9

What are Advantages and Disadvantages of Stratified sampling?

Answer 9

Ad:
Creates an accurate sample based on the research being done.
Dis:
requires a large proportion of population

Question 10

What are Advantages and Disadvantages of Cluster sampling?

Answer 10

Ad:
Cheap and easy
Dis:
Less accurate
Clusters may not be representative

Question 11

What are Advantages and Disadvantages of Opportunity sampling?

Answer 11

Ad:
Cheap and convenient
Dis:
May not be generalisable

Question 12

What are Advantages and Disadvantages of Quota sampling?

Answer 12

Ad:
Ensures the sample is representative over the factors identified
Dis:
May not be