The Math Behind Beautiful Color: David Aerne on Building Open-Source Color Tools

The Math Behind Beautiful Color: David Aerne on Building Open-Source Color Tools

Welcome to the final episode of Season #12 of the PolicyViz Podcast! Thanks so much for checking out the show this season and I hope you enjoy your summer. I’ll be back this fall with more great episodes. On this episode of the show, I’m joined by David Aerne, a freelance developer and designer based in Zurich who has spent years building a remarkable collection of open-source color tools. We dig into the difference between color models, color spaces, and gamuts, and David explains why thinking about color in three dimensions—like navigating a cylinder—can make choosing palettes so much more intuitive. We talk through several of his projects, including Color Names (a curated list of nearly 32,000 community-contributed color names), Rampensau for generating color ramps, and the playful RYB-inspired explainer that simulates how physical, “printy” colors look on screen. David shares his philosophy that we should integrate the systems that generate colors into our work, rather than freezing a static palette and losing the creativity along the way. Whether you build dashboards, design slides, or just love playing with color, this conversation will change how you think about picking your next palette. KEYWORDS: COLOR THEORY, COLOR PALETTES, DATA VISUALIZATION, COLOR TOOLS, HSL, HSV, RGB, COLOR MODELS, COLOR SPACES, OPEN SOURCE, GENERATIVE ART, COLOR RAMPS, DESIGN TOOLS, JAVASCRIPT, WEB DEVELOPMENT, PIXEL ART, POLICYVIZ PODCAST, DAVID AERNE Subscribe to the PolicyViz Podcast wherever you get your podcasts. Become a patron of the PolicyViz Podcast (https://patreon.com/policyviz) for as little as a buck a month Follow David Aerne on Bluesky and X (@meodai) and explore his open-source projects at elastiq.ch Follow me on Instagram, LinkedIn, Substack, Twitter, Website, YouTube Email: jon@policyviz.com

From Homework to Portfolio: NYC Open Data in the Classroom

Welcome back to the show! In this week’s episode, I chat with Christian Martinez, a faculty member at Brooklyn College and several other CUNY schools, and Shannon Joyce, a newly minted master’s graduate in psychological research—who, as we note at the top, literally graduated the day before we recorded. Christian shares how he redesigned his graduate stats and R course around NYC Open Data, building what he calls an “accidental author” process that transforms students’ weekly homework into portfolio books and, ultimately, chapters in a published student gallery. Shannon walks us through her own project exploring the relationship between mold complaints and domestic violence rates in New York City, and reflects on what it means to learn to code by asking questions you actually care about. We also dig into the NYC Open Data R package Christian and his students built together—now streamlined from 40 functions down to three and approaching 2,000 installs—and close with a lively conversation about whether open data skews too negative and what a truly positive city dataset might look like. KEYWORDS: NYC OPEN DATA, R PROGRAMMING, DATA VISUALIZATION, TEACHING DATA SCIENCE, OPEN DATA, CUNY BROOKLYN COLLEGE, R PACKAGE, DATA EDUCATION, OPEN EDUCATIONAL RESOURCES, DATA STORYTELLING, QUARTO, RSTUDIO, GRADUATE EDUCATION, DATA LITERACY, PUBLIC DATA Subscribe to the PolicyViz Podcast wherever you get your podcasts. Become a patron of the PolicyViz Podcast (https://patreon.com/policyviz) for as little as a buck a month Find Christian Martinez and all student work at NYCOpenDataLab.org. Find Shannon Joyce on GitHub (github.com/ShannonJoyce) and LinkedIn. Follow me on Instagram, LinkedIn, Substack, Twitter, Website, YouTube Email: jon@policyviz.com

Outlier 2026: What to Expect at This Year's Data Visualization Society Conference

Episode #310! This week I sit down with Jennifer Roscoe and Shrishti Vaish, two of the key organizers behind Outlier 2026, the annual data visualization conference hosted by the Data Visualization Society. We talked about what it takes to pull off a fully virtual, global conference, and why going virtual this year was a strategic choice, not a compromise. Jennifer and Shrishti walked me through the conference dates (June 23–26), the brand-new pre-conference data challenge in partnership with the United Nations, and the exciting new feedback and career clinic designed to give attendees a safe space for honest critique and professional growth. We also get into the behind-the-scenes logistics: the 30-person volunteer committee, the technology stack (mostly Google Sheets, if you were wondering), and the delicate art of playing Tetris with 34 talks across a 12-hour global schedule. Whether you’re a first-time attendee or a longtime DVS community member, this episode is your guide to making the most of Outlier 2026. KEYWORDS: DATA VISUALIZATION, DATA VIZ, OUTLIER CONFERENCE, DATA VISUALIZATION SOCIETY, DVS, DATA VIZ CONFERENCE, JENNIFER ROSCOE, SHRISHTI VAISH, VIRTUAL CONFERENCE, DATA STORYTELLING, DATAVIZ COMMUNITY, CONFERENCE PLANNING, CAREER CLINIC, INFORMATION IS BEAUTIFUL, DATA CHALLENGE, UNITED NATIONS DATA, POLICYVIZ PODCAST Subscribe to the PolicyViz Podcast wherever you get your podcasts. Check out the 2026 Outlier Conference [https://www.datavisualizationsociety.org/outlier]. Follow me on Instagram, LinkedIn, Substack, Twitter, Website, YouTube Email: jon@policyviz.com

Reimagining Civic Participation: The Digital Democracy Project

I talk with Ramon Perez, Executive Director of the Digital Democracy Project this week. DDP is a nonpartisan nonprofit using secure mobile voting technology to give citizens a real-time voice in legislation. Ramon explains how the platform lets verified, registered voters weigh in on bills being debated in Congress and their state house—and then scores legislators on how closely their votes match what their districts wanted. We dig into how AI, including a RAG-powered chatbot called VoteBot, helps everyday citizens parse thousands of pages of complex legislative text. We also discuss digital security, participatory budgeting, and Ramon’s ambitious goal of expanding the platform to all 50 state legislatures by 2027. KEYWORDS: DIGITAL DEMOCRACY, MOBILE VOTING, CIVIC TECH, LEGISLATIVE TRANSPARENCY, AI IN GOVERNMENT, RAMON PEREZ, DIGITAL DEMOCRACY PROJECT, VOTEBOT, PARTICIPATORY BUDGETING, VOTER ENGAGEMENT, LEGISLATOR ACCOUNTABILITY, POLICYVIZ PODCAST, CIVIC ENGAGEMENT, GOVTECH Subscribe to the PolicyViz Podcast wherever you get your podcasts. Become a patron of the PolicyViz Podcast [https://patreon.com/policyviz] for as little as a buck a month Follow Ramon Perez and the Digital Democracy Project at digitaldemocracyproject.org and download the Votes (VOATZ) app to participate. Follow me on Instagram, LinkedIn, Substack, Twitter, Website, YouTube Email: jon@policyviz.com

Mapping the Invisible: Inside the Atlas of Macroscopes

Welcome back to the show! This week, I sit down with three co-authors of the Atlas of Macroscopes—Katy Borner, Elizabeth Record, and Todd Theriault from the Cyberinfrastructure for Network Science Center at Indiana University—to explore what a macroscope actually is and how it differs from a standard interactive visualization. We trace the 20-year journey of the Places and Spaces: Mapping Science exhibit, from two-dimensional wall maps to the 40 richly interactive pieces featured in this stunning 11×14-inch MIT Press book. Along the way, we talk about design strategies for making complex systems legible to general audiences, the role of AI in data visualization, and what it takes to grab and hold attention on a museum floor. Each guest shares a personal favorite from the book—ranging from Smelly Maps to an Appalachian opioid overdose tool to a skills-landscape explorer—and we close with a look at the exhibit’s exciting third decade, focused on visualizing intelligences. KEYWORDS data visualization, macroscope, atlas of macroscopes, interactive visualization, Katy Borner, Indiana University, Places and Spaces, complex systems, information visualization, scrollytelling, AI and data visualization, opioid epidemic mapping, data communication, science exhibit, data science podcast Subscribe to the PolicyViz Podcast wherever you get your podcasts. Become a patron of the PolicyViz Podcast (https://patreon.com/policyviz) for as little as a buck a month Find the Atlas of Macroscopes [https://amzn.to/3PoaITJ] and explore the Places and Spaces exhibit at scimaps.org. Follow Katy Borner, Elizabeth Record, and Todd Theriault through Indiana University’s CNS Center. Follow me on Instagram, LinkedIn, Substack, Twitter, Website, YouTube Email: jon@policyviz.com