2.5: Graphs that Deceive

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It's common to see graphs displayed in a misleading manner in social media and other instances. This could be done purposefully to make a point, or it could be accidental. Either way, it's important to recognize these instances to ensure you are not misled.

You should always ensure that your graphs are not misleading.

Here are some common ways that graphs can be misleading.

Data is left out. Perhaps some of the data doesn't show the expected or hoped for results. Not using that data can make the graph look more convincing, but is unethical.
The graph isn't labeled. If the horizontal and vertical axes aren't labeled or if there is more than one variable and it's not labeled which one is which, the person reading the graph will need to make assumptions which may not be correct.
The graph isn't labeled correctly. Incorrectly labeling the axes or a variable can lead to a misunderstanding of what the graph means.
The scale of the graph is off. Either having a scale that is too large or too small can make the differences in variables seem much larger or smaller. Or not starting the scale at 0 could also amplify differences between variables.

Always check to make sure the graph you are reading doesn't use any common deceptive techniques to confuse the results being presented. Never use these techniques yourself.