Understandable Statistics 10th edition
By Brase and Brase
A graphical display should:
Show the data
Induce the viewer to think about the
substance of the graphic
Avoid distorting the message
Properties of Bar Graphs
Bars can be vertical or horizontal
Bars are of uniform width and uniformly
spaced
Length of bars represent value of variable
being displayed
Graph has title, labels for each bar and scale
for length of bar
Bar Graphs
Hospital Patients by Unit Bar graphs are the
5000 most effective type
of illustration when
patients per year
4000
the task is to display
Number of
3000
relative size, or to
2000 make a comparison
1000 of magnitudes
between categories.
0
Cardiac
Surgery
Emergency
Maternity
Intensive
Care
Care
Other Types of Charts
A Pareto chart is a bar graph in which the bar
height represents the frequency of an event.
In addition, the bars are arranged from left
to right according to decreasing height.
In a circle graph (or pie chart), wedges of a
circle display proportional parts of the total
population that share a common
characteristic.
Pareto Chart
Reasons for returns
• tool of quality 60
50
control 50
• start with a bar 40
chart 30
20
• arrange bars in 20
10
decreasing order 10 5
of frequency 0
• frequently used to e
e
er
ity
z
ik
Si
th
l
tL
ua
O
investigate causes
Q
n'
id
D
of problems
Pie Charts
shows division of
whole into
component parts
label parts with
appropriate
percentages of the
whole
Time Series Graphs
In a time series graph, data are plotted
in order of occurrence in regular
intervals over a period of time.
Time series data consists of
measurements of the same variable for
the same subject taken at regular
intervals over a period of time.
Time-series Graphs