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1. Module 6: Presenting Data:
Graphs and Charts
A Training Course for the
Analysis and Reporting of Data from
Education Management Information
Systems (EMIS)

2. Overview
Presenting Data: Graphs and Charts
Purpose of graphs and charts
Components of graphs and charts
Types of graphs and charts
Selection of data presentation
Using text to present data

3. Presenting Data: Graphs and Charts
Graphs and charts:
represent and summarize statistical information
in a visual manner to show patterns and trends
in the data
are useful for highlighting and presenting
important information
an ideal method for presenting statistical
information to non-technical audiences

4. Purpose of charts and graphs
Charts and graphs are used:
to visually represent information that cannot be
easily read and interpreted from a table
to show trends and changes in statistical data
to make comparisons between two different set
of data or when making to make predictions and
forecasts.

5. Advantages of charts and graphs
The advantages of charts and graphs are:
easier to understand than a table of numbers
highlight patterns and trends in the data
makes comparisons and analysis easy
representation of data using different types of
graphs and charts
allow for special designs
e.g. age-pyramids
and thematic maps

6. Components of charts and graphs
To understand and interpret the data represented
in a graph or chart :-
Graphs and charts should have:
 a title
 axis labels
 labels for subgroups
 footnotes
 references to source data

8. Characteristics of charts and graphs
Graphs and charts should have the following
characteristics:
present a key message
have a clear objective
use an appropriate type of presentation
have a simple and clear design

9. Types of graphs and charts
There are many different types of graphs and
charts
including:
Pie chart
Line graph
Bar chart
Area graph
Scatter plot
Maps

10. Pie chart
•Pie charts are used to
present categorical data
by describing the
percentage
distributions of
components within a
total
•The area of each slice of
the pie is proportional
to the relative share of
each item that makes
up the total

11. Pie chart No-Nos
Do not include too many slices
on the same pie chart as it may
make a pie chart difficult to
interpret
Do not use 3D pie chart designs
as these distort the size of the
slices and therefore
misrepresent the proportion of
the total.

12. Line graph
A line graph is used to
present time-series
data that shows
changes in values
from one time period
to another.
A single graph can
display multiple time-
series, with one line
for each data series or
sub-population.

13. Line Graph No Nos…
Do not graph too many data
series at once – regroup
categories
Do not use line graphs with
categorical data – use bar or pie
charts

14. Bar chart
Bar charts are used to
compare two or more
numeric values from
different sub-
populations
Bar charts display data
as rectangular bars with
lengths proportional to
the values that they
represent

15. Bar chart
Bar charts can be
vertically (column) or
horizontally oriented
(bar)
Horizontal bars are
used when there are
many categories of
data and each bar
requires a long label

16. Stacked bar charts
Stacked bar charts are
used to present values
that have components.
The entire length of each
bar indicates the total in
each group.
The lengths of separate
component bars show
both their absolute sizes
as well as comparison
with each other.

17. Area graph
Area graphs are
used to show
changes in total and
component values
over time.
An area graph is
created by drawing
lines to connect the
values of
component data
series, and then
stack them one on
top of another.

18. Area graph
For area graphs it is
important that:
the time scale is drawn
correctly
use a linear scale for the
time points

19. Scatter-plot
Scatter plots are used for
showing the relationship
between two variables
by plotting pairs of
values.
There is a strong
relationship between
values in a distribution
if they appear close to
the diagonal.

20. Scatter plot
Scatter plots can
be used as a data
visualisation tool
to identify outlier
data points
Both X
(horizontal) axis
and Y (vertical)
axis values need
to be numerical
values

21. Maps
A map represents the
geographical area,
drawn to scale, to
highlight the spatial
relationships
between objects and
indicators.
Maps are an excellent
way of displaying the
distribution of data
across geographical
areas.

22. Selection of data presentation
Choosing between tables, graphs and charts
largely depends on the audience to which you are
communicating the information:
For technical audiences, summary tables are an
accurate way of presenting data
For non-technical audiences, charts and graphs
may better represent data in visual form
For a mixed audience, it may be useful to
present the data in both table and graph form

23. TIPS for selecting tables or charts
Tables work best when the data presentation:
contains many data series
is used to compare individual values
requires precise values
contains multiple units of measurement
Graphs work best when the data presentation:
is used to identify patterns and trends
is used to communicate a key message
is used to visually show relationships in the data

24. Process of creating a graph or chart
Steps to create a graph or chart:
1. Organize and present data in a table
2. Calculate percentages, ratios and other
indicators
3. Create graph or chart to illustrate the data
STEP 1 STEP 2 STEP 3

25. Using text to present data
Tables, graphs and charts are usually referred to in
the narrative of a report by descriptive text.
Descriptive text:
explains and interprets the presented data for
the reader
provides a summary of the main trends or
patterns in the data
may provide an example from the table or
graph to highlight the key message

26. Five basic rules
When drafting a text to describe a table or chart:
1. Highlight key findings and meanings to capture
the reader’s interest
2. Write clearly and succinctly to describe the data
3. Be consistent in the use of language and style
throughout the report
4. Review the written text to eliminate
unnecessary repetitions
5. Focus on the main points and minimize
unnecessary details

27. Guidelines for descriptive text
Keep the summary short and to the point
Position text close to the table or chart to which it
refers.
Use key reference numbers e.g. Table 1 or Figure 1
Write in an objective manner when describing
data
Avoid using unnecessary technical terms
Be cautious when attributing causality to a factor

28. Writing TIPS
Avoid long sentences
Paragraph breaks
Commas provide pauses within a sentence
Minimize the use of brackets
Avoid repeating the same wording
Avoid unnecessary words and phrases
Keep the language simple
Be logical
Ensure that the use of articles is clear
Adopt conventions and keep to them

29. Exercise
Discuss:
What is the purpose of graphs and charts?
What are the components of graphs and charts?
What are the different types of graphs and charts?
How you select the type of data presentation?
Why do you use descriptive text to present data?