Seven Basic Data Viz Rules
Data visualization is being used more and more within organizations, especially when reporting, where you are explaining something: you are forwarding a message or telling a story with numbers.
So what makes a good presentation of data viz?
1 Who is your audience?
You need to have different approaches depending on your audience. Is the report intended for the Board, where the big picture is more valuable, or for line managers, who need to see the details? How much details do you need to include in your graphs and tables? Are you presenting the data in front of the audience, where you are going to tell the story and lead the audience live, or is the report distributed by email or in paper form?
2 What are you looking for?
It´s the most important thing: you must know what you are looking for. Make sure you understand the question before you create your table or graph. Once you know what to look for, build your table or graph around that. Also, you get the best result when you keep yourself to a question at a time.
3 How are you presenting it?
First of all, you must know what you are looking for. The report must be able to stand alone and know what you are looking for. Your audience must be able to get the message by looking at your graph. Explain your units of measure, label your axes, encode your quantitative data accurately. Start with the top left and work your way down to the bottom right.
If your graph is embedded in a body of text, most times you do not need to tell your story by inside the graph. However, if the graph is by itself and there is a story to be told, included small but powerful chunk of text inside the graph.
Be consistent with the placement and ordering, either alphabetically or by value.
4 Where is the data coming from?
Include your sources. This will increase the reliability of your tables and graphs, and gives your audience a chance to make further research.
5 Choose the right type of media display
Are you, let´s say, showing a reference, or a relationship or a trend and exception highlight? Your media display should reflect your choice of media display. Are you using a table, and if so, which table? Or are you using a graph, and if so, which graph?
6 Get rid of distractions
Ensure your graph is easily navigated. Avoid noise in your reports. Special effects tend to take the focus away from the message. Do not use 3D-graphs or shadows in your graphs. Opt to choose as few colors as possible, except when you want to highlight something, and instead use saturation of the hue, stay away from too bright colors. Do you need a border line? Are the grid lines necessary? Is the graph title repeated in the legends section? Make sure the the content in the axis labels is not tilted or vertical, as it makes it difficult to read them.
7 How is it going to be perceived?
When you are presenting multiple graphs or tables, do you want them to be seen as a group or separately? Object that are close together or connected (proximity), have similar shape or color (similarity), have a continuation together (continuity) or perceived as one group.