Data Visualization Basics for Students Dionisia de la Cerda Think about Your Message You want your audience to understand your message. This takes time. Think about your audience and plan your message. Give Yourself Enough Time Write your report, add in the basic information you need in table format. Bold sections of your paper that contain key pieces of your argument. These are the places where a graphic could help you tell your story. For each one think about your message. Don t just give your audience a table to read on their own. Use color, annotations, and titles to let your audience know what you want them to understand. Completing all the charts, tables and graphs at the end will also help you stay on track with being consistent. Pictorial Superiority Effect: Our brains take in a majority of information visually, so we learn complex ideas best with a visual guide pair with text. We retain and interpret more visually than we do verbally. Our working memory is limited when interpreting new information. Our working memory can hold a concrete picture both visually and verbally; however, abstract ideas can only be stored verbally. Be Consistent Use the same axis, scale, and language. Use the same font, color, and graph types. You do not want your audience having to relearn how to interpret your graphs. Be Redundant Authors make the mistake of assuming the reader wants to interpret the results themselves. They do not. You have a message and story you are telling with your data, so make sure your reader knows what that is. If you want them to notice that one category is bigger than the other because that is part of your discussion, then add an annotation pointing out the trend. Does it Pass the Squint Test? Can you squint at the graphic and still get a basic idea of the message? Keep It Simple With the graphic tools at your disposal it is tempting to do something fancy ; however, make the graph simple. Don t be tempted by 3D, multi color or overly complex graphics. One test is to have someone not familiar with your topic review you graphic. If you cannot explain what your graphic is trying to show in 5 minutes then it is too complicated. Page 1 of 5
Just Say No to Pie Pie graphs are OUT. People are terrible at estimating angles, and there is often a better way to convey your message. I have one example at the end of this handout; however, if you want more example google alternatives to pie charts Use Color Accent Colors are a great way to draw the reader s eyes to what you want them to know about the graph. If in your paper you discuss a particular trait you see in your data, color can help you make it stand out in the graphic. Here the author wanted people to know that a lot of evaluators do not eat breakfast. By using an accent color the reader is drawn to this fact. Source: From Stephanie Evergreen s presentation on Data Viz: http://p2i.eval.org/wpcontent/uploads/lightyourignite.pdf By making the one line red, and greying out the other lines the reader sees that the upward trending line is the point of discussion. Source: http://vis4.net/blog/posts/doing the line charts right/ Resources: A great way to pick out a color scheme for you graphics: http://colorbrewer2.org/ A link to some handouts I put together: http://tinyurl.com/datavizresources Page 2 of 5
Examples: Instead of a Pie Chart: Try a Bar Graph with a clear title, and subtitle. Stephanie Evergreen s Blog has a step by step on how to do this: http://stephanieevergreen.com/how torock the text in your data visualization/ Page 3 of 5
Instead of Sloped Lines to Show Change in Means Use a dumbbell dot plot. Step by Step Directions on how to make this is here: http://stephanieevergreen.com/how to make dumbbelldot plots in excel/ Page 4 of 5
Likert Scale Alternative It is not uncommon for a researcher to present likert scale results as a mean of all the responses; however, the American Statistical Association recommends stacked divergent bar chart for representing Likert scale data (see article in the dropbox file provide in the resources ) Word Clouds Word Clouds can be a fun way to present qualitative data. Some great online word cloud generators are http://www.wordle.net/create and http://www.tagxedo.com Page 5 of 5