Deviation From What? Visual Centers & Norms, and the Tradeoffs they conceal

Data visualizations need reference points. We anchor scales, smooth trajectories, define clusters, choose midpoints... these decisions are necessary; they make data legible. But in doing so, they also establish a center: a trajectory that looks typical, a midpoint that appears neutral, a dominant pattern that becomes the standard against which everything else is read.

This talk explores what happens once that center stabilizes. When a single trajectory becomes the implied norm, differences from it can appear irregular, lagging, or exceptional. At the same time, the trajectory itself compresses (and in many cases conceals or at the very least misrepresents) the policy decisions, resource constraints, and tradeoffs that produced it.

I will draw on examples from education and public policy dashboards (spaces where summary visuals shape how institutions and communities are understood). My aim is not to argue against abstraction or analytical rigor. Rather, I want to examine how visual encoding practices construct norms, often unintentionally. When divergence is framed relative to a stabilized center, it can be read as something to be corrected at the level of the unit being measured (thereby placing unfair responsibility or judgment on the individual), instead of prompting questions about structural segmentation or competing objectives.

The talk will move through three parts: first, how visual centers are constructed; second, how they shape interpretation in policy-facing datasets; and third, alternative and sometimes complimentary approaches that retain broad patterns while making structural tradeoffs and multiple trajectories more visible.

This topic matters to me because I work with institutional data where dashboards influence decisions about performance, funding, and accountability. I’m interested in how we can preserve clarity without allowing abstraction to quietly harden into normativity.

For practitioners and researchers in data visualization, I hope the talk offers a vocabulary for recognizing implicit centers, a way to think about the interpretive weight they carry, and practical ideas for designing with that awareness in mind.