Misleading Graphs

Image Source: http://www2.fiu.edu

The most common “trick” with graphs is tomake the scale not start at zero.This makes small differences look much bigger. Image Source: http://thinkingmeat.net

Sometimes the Scale does not start at zero,and the Graph is also put in a 3D perspectivewhich confuses our eyes. Image Source: http://www.math6.org

Image Source: http://www.his.washk12.org/

The Scale does not start at zero, and makes the houseprice in 2006 look about seven times higher than 1975,when it is really only about two and a half times higher.(eg. 160 000 in 2006 is about 2.5 times 60 000 in 1975). Image Source: http://www.brickonomist.net

In Picture Graphs, the items are sometimes all madedifferent sizes to trick our eyes into thinking we havemore of the bigger sized items. Image Source: http://www.bbc.co.uk

In this Picture Graph, the year 2000 picture is abouteight times bigger than the 1960 image. Howeverwhen we check on the vertical scale, year 2000 is onlytwo and a half times bigger. (2.5 x 100 = 250). Image Source: http://www.yale.edu

Trick or Treat ? In this Picture Graph, there isdefinitely a trick being done! From the vertical scaleMichael collected about twice as much candy asShayna, but his picture is about three times bigger. Image Source: http://www.yale.edu

This pie chart is totally incorrect. The sizes of thepieces of pie have not been drawn the right sizes. Image Source: http://www.visionjar.com

This non-standard pie chart is interesting. If“Cartera” was graphed properly as a piece of pie, thenit would only be a very thin slither, and not nearly asbig looking as the big circle drawn for it here. Image Source: http://dribbble.com

In this non-standard chart, it is very hard to work outwhat point they are trying to make or explain. Image Source: http://image.bayimg.com

The common ways to make a graph misleading are:• Scale not starting at zero.• Scale made very small to make graph look very big.• Scale values or labels missing from the graph.• Incorrect scale placed on the graph.• Pieces of a Pie Chart are not the correct sizes.• Oversized volumes of objects that are too big for the vertical scale differences they represent.• Size of images used in Pictographs being different for the different categories being graphed.• Graph being a non-standard size or shape.

Is this a Misleading Graph ?Image Source: http://mathspig.files.wordpress.com

http://passyworldofmathematics.com/

Misleading Graphs

by Passy World on Mar 18, 2012

Accessibility

Categories

Upload Details

Usage Rights

Statistics

Misleading Graphs Presentation Transcript