Avoiding the use of misleading graphs
Graphics convey much more information than words. Not everyone understands P-values or statistical arguments, but almost everyone can tell if one piece of a pie plot is larger than another piece of pie plot, or if two-line plots share a similar trend. However, there are many ways in which graphs can also damage the quality of a visualization or mislead readers.
In this section, we will examine two examples. Let's start with the first example – misleading graphs.
Example 1 – COVID-19 trend
The following graph is a screenshot taken in early April 2020. A news channel showed this graph of new COVID-19 cases per day in the United States. Do you spot anything strange?
The issue is on the y axis. If you look closely, the y axis tickers are not separated equally but in a strange pattern. For example, the space between 30 and 60...