Gary Klass has developed a great website related the topic of misleading and down-right dishonest graphs. Skim through last semester’s Section 13.3 lecture notes, then take a hard look at Klass’s “How to Construct Bad Charts and Graphs,” paying particular attention to what it takes to make bad charts and graphs. Professor Klass is currently constructing an updated site, which includes up-to-date, awful graphs. Several of these graphs include recommended revised versions.
Now it’s your turn (, of course!). Find one chart or graph that appears to be misleading or severely slanted. If you find the chart off line, please scan it then insert as a picture. If you find the chart online, provide a link to the site where the chart is located. Why is the graph misleading? If you were to revise the chart to make it appear more honest, what would you do?
Filed under: Original Problems | Tagged: graphs misleading
bad graph #1- http://www.math.sfu.ca/~cschwarz/Stat-301/Handouts/node12.html
This is a good example of a bad graph. The graph is missleading or just bad becuase it uses different numbers. The different numbers are circled on the graph. On one bar it uses the numbers 40,000- 49,000. On the next bar it uses the numbers 30,000 - 39,999. So the numbers are not even comparable. To help this graph become more accurate they should use only rounded numbers such as 39,000 instead of ugly numbers like 39,999.
Good example, KyLynn. (I bet others can find some good examples from that site, too, by the way!
)
bad graph http://www.thejabberwock.org/blog/2/roubik2.gif
This graph is a very bad graph. The graph is very wierd and misleading because of the bee flying around and his line does not even hit all the dots on the graph. Then the actual line again does not even hit all the dots on the graphs. The way that I think that the graph should be improved is try making the numbers from smallest to bigest if you want to leave it as a line graph and if you are going to have two lines make sure they hit all the marks on the graph. Don’t try to just make it pretty.
http://www.math.sfu.ca/~cschwarz/Stat301/Handouts/chart_fundraising.png
This is a good example of a bad graph. It is a bad graph because you are not told what the yellow and gray colors stand for. Also there is no side axis for the dollar amounts to be listed on for the comparisson of the heights of the bars. Also the dollar amounts should be rounded off so that they are easier to understand and easier to compare. Instead of using 26,078.294, 26,078 is much less to deal with and easier to look at.
From this graph it looks as though house prices have trippled in one year! It is misleading because the vertical axis does not start at 0.
http://gator.gasd.k12.pa.us/~smcgrail/myweb/powerpoint/misleading_graphs/ma03039.gif
Look at the ‘improved’ version of the same graph. This gives a much more accurate picture of what has happened.
http://gator.gasd.k12.pa.us/~smcgrail/myweb/powerpoint/misleading_graphs/ma03040.gif
http://gator.gasd.k12.pa.us/~smcgrail/myweb/powerpoint/misleading_graphs/ma03040.gif
This was a good example of a bad graph. I didn’t even notice what was wrong with it until I looked at the good one, this site give the good graph with the bad one so you can tell what is wrong with it.
http://www.gator.gasd.k12.pa.us
http://www.coolschool.ca/…/unit1/U01L02/ma03045.gif
To me this is not a very good graph. It does not tell you exactly what they are wanting you to know. They are different sizes and it doesn’t look like they are giving the right information. Where is the catergory for the people who do own a pet?
http://gator.gasd.k12.pa.us/~smcgrail/myweb/powerpoint/misleading_graphs/here_are_some_examples_of_mislea.htm
This is a whole page of misleading graphs and the reasons why.
One the first graph, at first glance I didnt realize WHY it was misleading until I read the reason. It doesnt start at 0-when I looked over the graph again it did seem odd. it went up 2 though it did look as though it doubled or tripled.
http://gator.gasd.k12.pa.us/~smcgrail/myweb/powerpoint/misleading_graphs/here_are_some_examples_of_mislea.htm
http://images.google.com/imgres?imgurl=http://www.coolschool.ca/lor/AMA11/unit1/U01L02/ma03045.gif&imgrefurl=http://www.coolschool.ca/lor/AMA11/unit1/U01L02.htm&h=290&w=400&sz=11&hl=en&start=24&um=1&tbnid=BHAIQUzF46iiXM:&tbnh=90&tbnw=124&prev=/images%3Fq%3Dmisleading%2Bgraph%26start%3D20%26ndsp%3D20%26um%3D1%26hl%3Den%26rls%3DRNWE,RNWE:2006-17,RNWE:en%26sa%3DN
This is an excellent group of examples. They each give the reasoning. Also, when you hover over the graph it changes to show the difference. I didnt see why, the first graph was misleading at first-then I took a second look after reading the reason why.
http://www.math.sfu.ca/~cschwarz/Stat-301/Handouts/node10.html
The bars are not proportionate to the percentage they represent. Also, the percent increase implied is not accurate according to the numbers.