Program Evaluation Toolkit for Harm Reduction Organizations
Data visualization refers to the act of translating evaluation data into a visual context to make it relatable and easier to understand. At its core, data visualization can be thought of as a combination of evaluation data (both qualitative and quantitative), the design (the visual representation), the story (the message that is being conveyed), and shareability (the mechanisms used to get the information out into the world). To be effective, the visualization of your data should:
When visualizing your data, it is helpful to select a visual that best aligns with the data that you are attempting to illustrate. Not doing so may make your data hard to understand. The table below provides an overview of when types of common visualization elements should be used.
Table (5.7). To compare one set of values to another, use:
| Tables | This consists of rows and columns used to compare variables. Tables can show a great deal of information in a structured way, but they can also overwhelm users who are simply looking for high-level trends. |
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| Bar charts | These graphs are divided into sections that represent parts of a whole. They provide a simple way to organize data and compare the size of components to one another. |
Table (5.8). To illustrate changes over time, use:
| Line graphs and scatterplots | These visuals show change in one or more quantities by plotting a series of data points over time. Line graphs utilize lines to demonstrate these changes, while scatterplots connect data points with line segments, stacking variables on top of one another and using color to distinguish between variables. |
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Table (5.9). To see the parts of the whole, use:
| Pie charts | A pie chart is a divided circle, in which each slice of the pie represents a part of the whole. The categories that each slice represents are mutually exclusive and exhaustive. Data with negative values cannot be displayed as a pie chart. |
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Table (5.10). To represent text from qualitative data, use:
| Word clouds | Word clouds or tag clouds are graphical representations of word frequency that give greater prominence to words that appear more frequently in a source text. |
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| Concept mapping | Concept maps are depictions of the relationship of multiple concepts. |
No matter which data visualization tool you choose, remember that the simpler and more straightforward the visual is, the more likely your audience will clearly understand what you are attempting to convey. The purpose of data visualization is to support the telling of your program’s story and/or call to action. If you are unsure if your data visualization is hitting the mark, it might be worthwhile to pull in members of your evaluation or program teams to review and provide feedback.
Here are some helpful resources for your consideration:
