Wednesday, May 5, 2010

Communicating with Numbers #1

It’s Hard to Compare Shapes.

Which piece of the pie is bigger – and by how much? It’s hard to say because the human eye finds it very difficult to judge how much bigger one shape is than another.

Pie charts and three-dimensional shapes may look attractive, but they won’t do a good job of presenting your data because the viewer won’t be able to tell how much bigger one quantity is than another.

On the other hand, a simple bar graph makes it easy for readers to compare one line length to the next.

See Also: Dynamic Tables and Graphs

2 comments:

Stephanie V said...

Oh dear. I'm challenged by graphs. I hope that you would advise that the actual words be included somewhere for those of us who take longer to process the visuals.

Penny said...

Graphs should only be used if they are easy to understand. It's important to have a clear title, a date, a source, and any other explanation that may be required. The focus should be on providing the reader with useful information - creating a pretty graphic is completely irrelevant. My handout on Dynamic Tables and Graphs provides additional, really helpful information.