Topic 2: intro to measurment of variables + proportions

Question 1

What are the types of variables in the UK?

Answer 1

1) Numeric
- Continuous
- Discrete
2) Categorical
- Normal
- Ordered
- Binary

Question 2

Describe numeric for type A

Answer 2

• Measurable quantity
• Continuous: any possible value in range e.g. temp
• Discrete: specific values within range = count of integers e.g. number of teeth

Question 3

Describe categorical for type A

Answer 3

• Sorted into categories based on qualitative description
• Normal: divided into categories no order e.g. brands of car
• Ordered: divided into categories in ordered manner e.g. educational level
• Binary: 2 categories = yes/no

Question 4

What are the types of variables in the US?

Answer 4

1) Numeric
- Interval scale
- Ratio scale
2) Categorical
- Nominal scale
- Ordinal scale

Question 5

Describe numeric for type B

Answer 5

• Interval: values graded equal increments BUT no baseline e.g. temp in Celsius
• Ratio: same as interval but with true 0 baseline e.g. temp in Kelvin

Question 6

Describe categorical for type B

Answer 6

• Nominal scale: divided into different categories with no order e.g. country of origin
• Ordinal scale = divided into different categories in ordered manner e.g. income

Question 7

Explain the use of a bar chart

Answer 7

• Displays distribution of categorical variable
  -Shows counts for each category
• Next to each other for comparison
• Same width + equal spaces
• Can be clustered

Question 8

Explain the use of pie charts

Answer 8

• Show total sample as circle
• Pieces of circle = size proportional to faction of each category