What are some common data visualization pitfalls and how to avoid them?

I have found that when I present to a room with mixed hierarchies, associates up to C Suite, it is important to describe the chart in multiple ways. It can even be effective to have more than one chart showcasing the data in different ways. The associates may care about the proportion of sales and the C Suite may care about the relative value, for instance.

Here are some of my favored chart types and what are they good for. - Bar Charts: Compare values across categories (e.g., sales figures). - Line Graphs: Show trends over time (e.g., stock prices). - Pie Charts: Display proportions (e.g., market share). - Area Charts: Depict cumulative trends (e.g., website traffic). - Marimekko: Analyze segments by revenue and profit. - Waterfall Charts: Track cumulative effects (e.g., budget changes). - Scatter Plots: Visualize relationships (e.g., ad spend vs. sales). - Bubble Charts: Compare dimensions (GDP, population, happiness). Remember, simplicity ensures impact! ????

Truncated axis is important for waterfall charts though, it allows us to emphasize significant changes while maintaining clarity.

The data and information presented needs to directly contribute to the original question or intention of the analysis. If not directly, tangentially to support one of the direct contributions. Clutter, noise, and superfluous information can distract the recipient and cause confusion and frustration. Charts and visualizations can be powerful tools to help relay the point of the presentation but they need to be simple, direct, and purposeful in their message. Highlighting key points of analysis or expanding on changing trends can set your visualizations apart from cluttered and confusing dashboards which just grab raw data and present it without insight. YOU need to add value to the process through insight, analysis, and creativity.

In presentation settings, it is crucial to recognize that visual examples divide the audience's attention from the spoken content. If the on-screen information is overly complex, the audience may become absorbed in deciphering the slide, detracting from the verbal message being conveyed. Clarity and simplicity in visual materials are imperative to maintain audience focus on the presenter's spoken discourse.

In my experience, effectively highlighting focus areas in charts is crucial for audience engagement. To achieve this, I employ techniques such as varying colors, sizes, and shapes. This approach helps to draw the audience's attention to the specific areas we want to emphasize. For instance, in a column chart displaying data for the entire year, from January to December, I might use a darker color, like dark blue, for the months in Q4 (October, November, and December). The remaining months would be represented in a more subtle color, such as light blue. This visual contrast ensures that the audience’s attention is immediately drawn to the key area of focus.

Balance clarity and complexity. It’s often very tempting to layer multiple data views into a single visualization which may make it aesthetically beautiful and artfully designed, but make it difficult to understand for the desired audience. Design with a bias towards simplicity and clarity - as well as beauty - to make sure that your visualization speaks for itself as much as possible.