Give the person's question somewhere to go.

A fixed representation chooses what to show. An interactive one can let a person inspect a relationship, follow a detail, or vary a condition relevant to the model.

The useful interaction begins with the person's purpose.

What should they be able to understand? Which action would make that understanding more accessible? What should remain clear about the model's scope and assumptions?

An interface can invite curiosity. It can also shape what the person believes the system represents. That makes the relationship between model and experience important.

Howard Pearlmutter has worked across educational software, graphics, simulation, scientific visualization, enterprise applications, and human interfaces.

His NASA study examined human interaction with dynamic simulation. An energy-conservation videogame for Disney EPCOT connected learning with an active experience. Later software made complex factory designs inspectable to executives through animated virtual reality and web-enabled reports.

These were different audiences. Each needed a useful way into computational capability.

For an ecological subject, the interaction may help someone follow a flow, examine a boundary, or compare states over time. It should make the important distinction easier to question, not merely add controls to a picture.

Read EPCOT, NASA, and the atlas.

A visual inquiry can clarify the purpose. A prototype can then test whether the representation helps the intended person understand more.

Start with the question the person brings. Design a way for the model to respond usefully.