# Interpreting Bar Charts and Pie Charts - PowerPoint PPT Presentation

PPT – Interpreting Bar Charts and Pie Charts PowerPoint presentation | free to view - id: 4ca336-ZDc5Y

The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
Title:

## Interpreting Bar Charts and Pie Charts

Description:

### Interpreting Bar Charts and Pie Charts Interpreting Bar Charts and Pie Charts In this presentation Bar charts Pie Charts Interpretation Guidelines Bar Charts Bar ... – PowerPoint PPT presentation

Number of Views:254
Avg rating:3.0/5.0
Slides: 12
Provided by: Distr98
Category:
Transcript and Presenter's Notes

Title: Interpreting Bar Charts and Pie Charts

1
Interpreting Bar Charts and Pie Charts
2
Interpreting Bar Charts and Pie Charts
• In this presentation
• Bar charts
• Pie Charts
• Interpretation Guidelines

3
Bar Charts
• Bar Charts are used to display qualitative data
• Bar charts may display
• Counts (or frequencies)
• Percentages
• Proportions
• This allows comparison between categories.

4
Bar Charts
• The vertical scale is the frequency, relative
frequency, or percentage.
• This is critically important to recognize and
should be labeled.
• Frequencies are raw counts. That is, how many
individuals prefer each of the colors.
• Relative frequencies are really proportions
(usually decimals). To find the relative
frequencies, divide the frequency by the total
(for red, 11/25 or .44).
• Percentages are relative frequencies expressed as
percentages (for red, 44).
• See the example.

5
Bar Charts
• The horizontal scale shows the different
categories (sometimes multiple categories are
lumped together into an other category)..
• All bars should have the same width.
• There are gaps between the bars (since there is
no connection between them)
• Categories may be listed in any order.
• More complicated bar charts exist (such as
stacked or side-by-side).

6
Bar Chart Example
Back to slide 4 on Bar Charts
7
Pie Charts
• A circle is divided up proportionately to show
what percentage of the total each category
represents.
• They convey information regarding only the
relative size of categories (because of this,
they may mislead as totals remain unknown).

8
Pie Chart Example
9
Interpretation Guidelines
• Carefully read all labels (title, axes, bars, pie
segments, etc.) including the units and scale (be
sure to note the scales starting point).
• Identify (if possible) the source of the data. Is
there sufficient reason to suspect the source may
be attempting to persuade? In what way?

10
Interpretation Guidelines
• Consider and watch for extreme values or other
possible anomalies.
• Do the bars or pie sections represent counts or
relative counts?
• If there are multiple displays, are their scales
and axes consistent?

11
Interpreting Bar Charts and Pie Charts
• This concludes the presentation