Hard as it may be to master data analysis, honest unbiased reporting is even more difficult.
We all make mistakes, and quite a few of us give in to the temptation to mislead others for personal gain. While mistakes are par for the course, deliberate manipulation is not.
Charts are one of the most common data visualization choices. It’s not uncommon for people to “distort” reality either by mistake or intentionally when presenting bar, line or other charts. In my career, I saw people spot and correct charting mistakes and make “clever” misrepresentations designed to help someone get ahead.
Labeling of X and Y axes can be misleading. The context of what’s being presented can be made unclear. Cherry picking is a common practice for making things look better than they really are. Misusing charting conventions can “trick” people into seeing something that isn’t there such as a pie chart seemingly showing a favorable picture overall when, really, the chart is focused only on a small subset without an accompanying explanation.
This brings me to the point I am trying to make – be extremely vigilant with analytics. It’s just as dangerous as it is helpful. If you know what you are doing or if you are not very good at it, the result can be a disaster just the same.