Find two examples of “badly” designed graphs from outside sources. They can be from a magazine article, a book, a research paper, or a website. If the source is printed material, you can cut out the actual page, or photocopy it, or scan it. If it is from a website, you can print it out or do a screen capture.
Perform these tasks:
a) For each graph, list what is wrong with the graph.
b) Choose just one of your “bad” graphs and re-do it by hand either on graph paper or via a graphing program. Fix all of the things that are wrong with the original graph. You are allowed to change the type of graph if that enhances understanding of the data.
Here are additional requirements:
Each graph should be from a different source, e.g., one from a book and another from a website.
In addition to submitting a copy of the original graph, include enough of the text around the graph to show its context.
Only submit graphs that are substantially bad! Each graph should have at least two major things wrong with it. The worse, the better!
The best way to analyze a graph to see if it is "good" or "bad" is to look at what makes a good graph. A presentation out of a university in New Zealand seemed to have a good summary. In your own graphs, you'll want the following:
- Enough data to be reasonably expressed in a graph (2 or 3 values might be better just written in the text)
- Data must be good and relevant
- Presentation must not be too complex (overly-done 3D effects, multiple axis breaks, etc. should be avoided)
- Axes should be appropriately labeled, with breaks placed in a reasonable way (having too small of a range of values not starting at zero can overstate some changes or make variances seem larger than they are)
- Watch for distortion, too, where actual values may be different than how they are presented. This might often be used to either make a point or exaggerate a finding.
- Finally, of course, you want the basics: Labelled axes, units, linear or logarithmic scale on axes, a title or caption, a source for the information if the author did not obtain it him or herself, and a legend if more than one relationship is being demonstrated.
I hope this helps for your assignment! There are plenty of "bad" graphs out there. You'll often see exaggeration being used in charts with a political theme, and often magazines will show graphs ignoring some of the basic conventions. You'll be able to find a couple without much effort.