Data Collection

Question 1

What is a population?

Answer 1

• the whole set of items that are of interest

Question 2

What is a census?

Answer 2

• observes or measures every member of a population

Question 3

What is a sample?

Answer 3

• a selection of observations taken from a subset of population which is used to find out information about the population as a whole

Question 4

What are the advantages and disadvantages of censuses and samples?

Answer 4

Question 5

What is a sampling unit?

Answer 5

• individual units of a population

Question 6

What is a sampling frame?

Answer 6

• sampling units of a population are individually named or numbered to form a list which is the sampling frame

Question 7

What are the three methods of random sampling?

Answer 7

• simple random sampling
• systematic sampling
• stratified sampling

Question 8

What is systematic sampling?

Answer 8

• the required elements are chosen at regular intervals from an ordered list

Question 9

What is stratified sampling?

Answer 9

• the population is divided into mutually exclusive strata and a random sample is taken from each

Question 10

What is simple random sampling?

Answer 10

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

Question 11

What are the advantages and disadvantages of systematic sampling?

Answer 11

Question 12

What are the advantages and disadvantages of stratified sampling?

Answer 12

Question 13

What are the two types of non-random sampling?

Answer 13

• quota sampling
• opportunity sampling

Question 14

What is quota sampling?

Answer 14

• a sample is selected that reflects the characteristics of the whole population

Question 15

What is opportunity sampling?

Answer 15

• taking samples from people who are available at the time the study is carried out and who fit the criteria you are looking for

Question 16

What are the advantages and disadvantages of quota sampling?

Answer 16

Question 17

What are the advantages and disadvantages of opportunity sampling?

Answer 17

Question 18

What are quantitative variables/data?

Answer 18

• variables or data associated with numerical observations

Question 19

What are qualitative variables/data?

Answer 19

• variables or data associated with non-numerical observations

Question 20

What is a continuous variable?

Answer 20

• a variable that can take any value in a given range

Question 21

What is a discrete variable?

Answer 21

• a variable that can take only specific values in a given range