Chapter 3

Question 1

Graphical techniques to describe
nominal data

Answer 1

A relative frequency distribution lists the categories and the proportion with which each occurs.

Question 2

Pie chart - Calculating manually

Answer 2

To construct a pie chart, we need to calculate the size of each slice of the circle. Angle

Angle = the percentage of a category X 3.6

25.1 × 3.6 = 90.4^o

Question 3

Types of Graphical charts used to describe nominal data

Answer 3

Bar chart: used compare the size or frequency of various categories.

Pie chart: If the focus is on the distribution (the change in market share) of each category.

Question 4

Component bar chart

Answer 4

A component bar chart represents all categories within a single bar.

Component bar charts offer a good alternative to using
two pie charts, when a comparison of two breakdowns is
desired.

Question 5

Graphical techniques to describe ordinal data

Answer 5

When the data are ordinal (or ranked), treat the data as nominal and use a bar or pie chart.

Question 6

Describing the relationship between two nominal variables.

1/ A cross-classification table is used to describe the
relationship between two nominal variables.

Answer 6

2/ The frequencies can be depicted in graphical form using a bar chart.