1.1 Data collection

Question 1

Population

Answer 1

The whole set of items that are of interest

Question 2

Raw data

Answer 2

Information obtained from a population

Question 3

Census

Answer 3

Measures or observes every member of a population

Question 4

Census disadvantages and advantages

Answer 4

Advantages:
. Results should be completely accurate

Disadvantages:
. Time consuming and expensive

Question 5

Sample disadvantages and advantages

Answer 5

Advantages:
. Less time consuming
. Cheaper

Disadvantages:
. Data may not be accurate (small sample size)

Question 6

Sampling units

Answer 6

Individual units of a population

Question 7

Sampling frame

Answer 7

A list of sampling units

Question 8

What are the 3 types of random sampling

Answer 8

. Simple random sampling
. Systematic sampling
. Straisfied sampling

Question 9

Simple random sampling

Answer 9

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

Question 10

Systematic sampling

Answer 10

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

Question 11

Stratisfied sampling

Answer 11

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

Question 12

Simple random sampling advantages and disadvantages

Answer 12

Advantages:
. Free of bias
. Easy and cheap

Disadvantages
. Not suitable for large samples
. Sampling frame needed

Question 13

Systematic sampling advantages and disadvantages

Answer 13

Advantages
. Simple and quick to use
. Suitable for large samples

Disadvantages
. A sampling frame is needed
. Bias introduced if sampling frame is not random

Question 14

Stratisfied sampling advantages and disadvantages

Answer 14

Advantages
. Sample accurately reflects the population

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

Question 15

What are the 2 types of non - random sampling

Answer 15

. Quota sampling
. Opportunity sampling

Question 16

Quota sampling

Answer 16

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

Question 17

Opportunity sampling

Answer 17

Sample is taken from people who are available at the time of study and who fits the criteria you are loading for

Question 18

Quota sampling advantages and disadvantages

Answer 18

Advantages
. No sampling frame needed
. Efficient
. Cheap

Disadvantages
. Population must be divided into groups which can be costy
. Can introduce bias

Question 19

Opportunity sampling advantages and disadvantages

Answer 19

Advantages
. Easy to carry out
. Cheap

Disadvantages
. Unlikely to provide a representative result

Question 20

Types of data

Answer 20

Qualitative data
Quantitative data

Question 21

Quantitative data

Answer 21

Data associated with numerical observations are called quantitative data

Question 22

Qualitative data

Answer 22

Data associated with non-numerical observations are called qualitative data

Question 23

Continuous variable

Answer 23

A variable that can take any value in a given range is a continuous variable

Question 24

Discrete variable

Answer 24

A variable that can onlyy take specific values is a discrete variable