Isaac Reyes on the Key Principles of Data Storytelling at ODSC East 2018 Isaac Reyes on the Key Principles of Data Storytelling at ODSC East 2018
Where Cole in The Sixth Sense sees dead people, Isaac Reyes sees bad charts. In his role as founder and data scientist at DataSeer... Isaac Reyes on the Key Principles of Data Storytelling at ODSC East 2018

Where Cole in The Sixth Sense sees dead people, Isaac Reyes sees bad charts. In his role as founder and data scientist at DataSeer Inc., Reyes helps individuals and businesses better understand and convey the messages hidden in data. And in his keynote at ODSC East 2018, Reyes shared the key principles of data storytelling – the art of turning slide decks chock full of numbers and charts into data stories that are clear and impactful. Here were some of his most trenchant insights:

Slide copyright Isaac Reyes, ODSC East 2018
Reyes suggests that step zero of the data storytelling process is to ask oneself about the target audience; who is my audience and what do they need to know? The audience should be thought of as “the hero of your data story,” in such a way that the message is clear and understandable to them. So for example, in a presentation to business leaders, Reyes suggests making things as direct as possible. Don’t take the advice of your college statistics professor on summary titles, rather, entitle graphs based on the message they’re supposed to convey:Slide copyright Isaac Reyes, ODSC East 2018

Having placed the audience at the center of your data story, it’s time to start creating and refining the visualizations which will carry the narrative. Reyes’ approach draws on the Gestalt laws of visual perception, named after the famed German Gestalt psychologists like Kurt Koffka and Max Wertheimer, who sought to understand how humans acquired and maintained meaningful perceptions through sight. Two such principles that are particularly relevant to data visualizations include:

  1. The Law of Proximity, which says that things that are close together seem to go together,
  2. The Gestalt Law of Similarity, which holds that things that are colored the same appear to go together

Thus, color and spacing ought to be used strategically to help deliver the message of the data story at hand. In particular, careful use of colors and weightings can distinguish the most important chart elements from the rest. A problem with common graphing tools is that they give equal color importance to every data unit. But think of your favorite literary tale; does every character have the same importance? Finally, Reyes channels Edward Tufte, the statistician who pioneered many modern techniques for data visualization, in urging clients to remove unnecessary elements or “chart junk.” Any ink that’s there that’s not showing or contextualizing the data, Reyes suggests, is very likely superfluous.

Bringing it all together, Reyes shows how a messy plot attempting to convey a message about Apple’s revenue growth in China can be transformed into a clear, concise, and impactful data story:

Before:

Slide copyright Isaac Reyes, ODSC East 2018

After:

Slide copyright Isaac Reyes, ODSC East 2018

With a knowledge of these principles and some practice, Reyes suggests that all data scientists can learn how to tell great data stories.

Key Takeaways:

-Data Storytelling is the process of using data, visualizations, and narrative tools to send messages and communicate insights about data.

-Effective data storytelling revolves around one’s target audience, best thought of as the protagonist of the story being told. For example, the best titles for charts and visualizations depend on the audience and what they need to know.

-Design principles for coloration and spacing based on the Gestalt laws of perception help guide an audience through a data story.

-Always be wary of “chart junk,” or elements that don’t add to the message behind a chart.


Interested in hearing more in-depth discussions from leaders in the data science and artificial intelligence space? Check out ODSC’s upcoming conferences in San Francisco and London and register to be in the know.

Alex Amari

Alex Amari

I’m a graduate student at Oxford University pursuing an MSc in Social Data Science with the ultimate goal of working in tech entrepreneurship.