The idea
Glossary
Terms I coined or use in a specific sense. Every term has its own link, ready to share or cite.
- Cognitive distance
- The degree of mismatch between the conceptual structure that a system requires for correct interpretation and the mental model that a user actually constructs.
- Plainly How far apart a system’s logic and your picture of it are.
- See also Cognitive load,Mental model,Required model
- Cognitive load
- The mental effort a task demands. Low load means a task feels easy. It says nothing about whether the person understood what happened.
- See also Cognitive distance,Easy but opaque
- Mental model
- The picture a person builds of how a system works, from what it shows them and what they already know.
- See also Required model
- Required model
- The understanding a system actually needs from people for them to interpret it correctly. Drawn on this site as a dashed circle.
- See also Mental model,Cognitive distance
- Easy but opaque
- Low cognitive load with high cognitive distance: people finish the task and still can’t explain what happened. The failure that effort and completion metrics miss.
- See also Cognitive load,Cognitive distance
- Cognitive Distance Index (CDI)
- A 0 to 100 score across four dimensions: perceived understanding, predictive accuracy, interaction confidence and conceptual transparency. Bands: 0 to 25 strong alignment, 26 to 45 early warning, 46 to 65 needs attention, 66 to 100 serious misalignment.
- See also Cognitive distance
- Accessibility debt
- The cost that builds up when a system passes accessibility checks but still asks people to carry its complexity. Like technical debt, it grows quietly and is paid later, by the people using it.
- See also Cognitive distance
- Register
- The level of language a system uses, from plain to institutional. In the Everyday Services Study, the register is the only variable that changes between arms.
- See also Cognitive distance