Data Collection/sampling

Question 1

Define population

Answer 1

The whole set of items that are of intrest

Question 2

Define Raw data

Answer 2

The information obtained from the raw data

Question 3

Define Census

Answer 3

Measures or observes every member of the population

Question 4

What are the advantages of a census?

Answer 4

The results are completely accurate

Question 5

What are the disadvantages of a census?

Answer 5

Time consuming/ expensive

Question 6

What are the advantages of using a sample?

Answer 6

Cheaper/ less time consuming

Question 7

What are the disadvantages of using a sample?

Answer 7

May not be accurate (as sample size is small)

Question 8

Define sampling units

Answer 8

The individual units of a population
(E.g. students)

Question 9

Define Sampling frame

Answer 9

A list of the sampling units (e.g. Register)

Question 10

How many random samplings are there and what are the names?

Answer 10

3:
Simple random sampling
Systematic sampling
Stratified sampling

Question 11

What is simple random sampling?

Answer 11

A simple random sample of size n is one where every sample of size n has an equal chance of being selected

Question 12

Advantages of simple random sampling

Answer 12

Free of bias/ easy and cheap

Question 13

Disadvantages of simple random sampling

Answer 13

Sampling frame needed/ not suitable for large samples

Question 14

What is Systematic sampling?

Answer 14

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

Question 15

Advantages of Systematic sampling

Answer 15

Simple and quick to use/ suitable for large samples

Question 16

Disadvantages of Systematic sampling

Answer 16

Sampling frame is needed/ bias introduced if sampling frame is not random

Question 17

What is Stratified sampling?

Answer 17

The population is divided into mutually exclusive strata (groups), and a random sample is taken from each

Question 18

Advantages of Stratified sampling

Answer 18

Sample accurately reflects the population

Question 19

Disadvantages of Stratified sampling

Answer 19

Population must be clearly classified into distinct strata (time consuming)

Question 20

How many non-random sampling are there and what are the names?

Answer 20

2:
Quota sampling
Opportunity sampling

Question 21

What is Quota sampling?

Answer 21

An interviewer or researcher selects a sample that reflects the characteristics of the whole population

Question 22

Advantages of Quota sampling

Answer 22

Efficient/cheap/ No sampling frame needed

Question 23

Disadvantages of Quota sampling

Answer 23

Can introduce bias/ population must be divided into groups which can be costly

Question 24

What is opportunity sampling?

Answer 24

A sample is taken from people who are available at the time of study and meet the criteria of what you are looking for

Question 25

Advantages of opportunity sampling

Answer 25

Easy to do/ cheap

Question 26

Disadvantages of opportunity sampling

Answer 26

Unlikely to provide a representative result

Question 27

Define quantitive data

Answer 27

Data associated with numerical observations

Question 28

Define qualitative data

Answer 28

Data associated with non-numerical observations

Question 29

Define continuous variable

Answer 29

A variable that can take any value in a given range

Question 30

Define discrete variable

Answer 30

A variable that can only take specific values