Data Visualization: Charts for Beginners
When you're new to a subject, you seek guidelines that help you master the content. Creating charts is no exception. The purpose of a chart is to package information in a way that makes it quickly understandable. The thing that makes charts so useful is that they provide a quickly recognizable shape for your data. Think about that for a moment. Each graph you create has its own shape that is dictated by the data inside it. It's a visual explanation of a story.
Here are a few rules to get you off to a fast start:
Employ simplicity. Simplicity is the key to creating effective data visualizations. You should focus on using simple charts that are easy to digest. You won't get points for most amount of data displayed.
Display only the most important information. When you're new to charting, you may want to put in a lot of information so that you don't leave out anything of value. Resist this urge, because people can take in only so much information before their eyes glaze over.
Require little explanation. Don't make things so complicated that your users require a manual to understand what you're trying to convey. If you can't get something at a glance, it's too complicated for your reader.
Don't overload your data. It's important to avoid overloading your data visualization, but the trend toward the use of mobile devices makes this practice even more important. Mobile devices reduce the screen real estate to almost half of what's available on a desktop. Typically, a visualization isn't manipulated on a mobile phone; it's only viewed.
Stay away from 3-D. At some point in your data career, you may become a whiz at depicting charts in 3-D. However, it's recommended that you avoid this type of chart until you get more experience under your belt.
Next, you want to know what elements make up a good chart so that you can incorporate those elements:
Labels: Make sure to include labels for everything that isn't readily apparent. Labels are so important, yet many people forget to add them. Whether it's the title of the chart, the chart legend or the labels for the axes, letting users know what is being displayed is vital. Users typically look at the title of a chart before the actual chart, so be aware that you need one.
Color: Choosing the correct colors for your chart is critical. Whether you are displaying different quantities or pointing out specific measures, choosing appropriate colors is an absolute must. At a glance, most users are likely to focus on brighter colors first, sometimes completely overlooking less highlighted colors, such as gray. Strategically using the right colors in your chart guides your users and adds value by enabling them to decide what to focus on first.
Chart Type: Choosing the correct chart to tell the story of your data is quite a challenge. It's not surprising that the use of pie charts is so highly debated. Many newbies tend to go with what makes their data look pretty, often choosing the wrong chart for the wrong reasons.
The following figure shows how you might set up a chart to display some data on the x- and y-axes. In the figure, each axis is clearly labeled in its correct position.
Always include the source of the data at the bottom of the chart if the chart will be viewed outside your company.