“Making an evidence presentation is a moral act as well as an intellectual activity. To maintain standards of quality, relevance, and integrity for evidence, consumers of presentations should insist that presenters be held intellectually and ethically responsible for what they show and tell. Thus consuming a presentation is also an intellectual and a moral activity.”
Edward Tufte, Beautiful Evidence
This quote encourages me to assume ethical responsibility when using data to convey a specific message through information. Sometimes, data are misrepresented and can be done on purpose or just by a honest mistake. When it is done on purpose, it is to distort the data and to show something else. If someone wants to prove an argument, he may reach for the first bit of evidence but when closely examined can be very little supportive.
Below is a good example of misrepresentation of data by Nathan Yau:
Fox News used this chart to show the change in the top tax rate if the Bush tax cuts expire. They show the difference between now and for 2013. The height of the 2013 bar is around five times higher. But it is not the case. When the chart is carefully examined, the vertical axis starts at 34 not at zero. The first thing we do when we look at a bar chart is to compare the height of the bars, thus it is misrepresentation of data.
When the bar chart is done properly, with the vertical axis starting at zero, it can be seen that the difference between the two is not 5 times but only 4.6%.
Data can also be misrepresented if they are partly chosen from a whole set of data and therefore the outcome is completely distorted.
Tufte, Edward (2006) Beautiful Evidence, Connecticut: Graphics Press LLC.
Yau, Nathan (2012) Visualize This: The Flowing Data Guide to Design, Visualization, and Statistics, Indiana: Wiley Publishing.