misleadinggraphs press ctrl-a ©2009 – not to be sold/free to use stage 5 year 9
TRANSCRIPT
MisleadingMisleadingGraphsGraphs
Press Ctrl-APress Ctrl-A©2009 – Not to be sold/Free to use
Stage 5 Stage 5 Year 9Year 9
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Misleading Graphs
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Avera
ge H
ou
se P
rice
Massive Increase InHouse Prices this Year
1998 1999Year
Displaced Axes
The increase in price was not as big as it appeared to be.
20 000
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80 000
Avera
ge H
ou
se P
rice
1998 1999Year
0
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0
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Pizza Hot DogsHamburgers
Favourite Food
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Misleading Graphs
Displaced Axes
950
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Pizza Hot DogsHamburgers
Favourite Food
Nu
mb
er
of
Vote
s
Nu
mb
er
of
Vote
s
The number of votes appears significantly
here.
The number of votes appears not so
significantly here.
4
Misleading Graphs
Exaggerated use of Area or Volume.
Number of Singles Sold
1995 19961997 1998
The Brown column looks bigger than the purplepurple column. .But is it?
Number ofSingles Sold
1995 1996 19971998
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This is bad.This is bad.The various sized pictures distorts
the graph.
Misleading Graphs
All pictures must bethe about the same size.
(Area)(Area)
Dog:
Cat:
Horse:
The Exaggerated use of Area or Volume.
Key:5050 5050 5050
Dog:
Cat:
Horse:
Key:5050 5050 5050
This is much better
6
Misleading Graphs
Sales at Gerry’s Milkbar have doubleddoubled from 2007 to 2008.
2007 2008
The 2008 volume is eight times bigger than the 2007 volume.
Exaggerated use of Area or Volume.
7
Misleading Graphs
Irregular Scale Axes
1993, 1996 and 1998 1993, 1996 and 1998 are missing.are missing.
8
Misleading Graphs
Irregular Scale Axes
1993, 1996 and 1998 1993, 1996 and 1998 are added.are added.