Perceiving and Representing Structured Information using Objects

Organization Image based theories Structural 3D theories Object perception: Object displays

Image Based vs Structure Theories Template theories based on 2D image processing In structural theories we extract the structure of a scene in terms of 3D primitives

Template theories A template with simple morphing operations

Objects as patterns of (2D) patterns

Scenes (gist in 100 msec) Patterns of patterns Torralba and Oliva

Properties of Image Recognition Remarkable image recognition memory Up to 5 images for second in object identification Applications in image searching interfaces RSVP Rapid serial visual presentation

Perception of object structure

Geon Theory

Geon Theory 3D Primitives “Geons” Structural skeleton Shape from shading is also primitive

How Does the Brain Find Geons?

Canonical Views To make things clear both component parts and the critical joints must be clear

Processing stages for recognition

The Geon Diagram Pourang Irani 3D shape primitives for architecture - entities and relationships Surface texture and color for attributes

Pattern finding & Recognition 13% errors: 4.3 sec sub-structure 22% memory errors 26% errors 7.1 sec sub-structure 42% memory errors

Semantics On top of - relies on Underneath – support, foundation Inside – containment (private code) Attachment points (external interfaces; part_of relationships) more than topology mid Upper Lower

Natural semantics Instances Dependency Multiplicity Strength of Relationship

The Object Display (Wickens) Use complex objects to fuse variables Map entities to object parts Map structure to object structure Can be pictorial (simplified) – an engine + fuel tank Map attributes to object attributes - color, size, motion etc.

Object Display Vol : 45 L Temp: 45 deg Flow: 20% Solids: 23% 100 L 0.2/1.0 45 deg Solids: 23%

Approx 1/3 errors with anesthiologists Dr George Blike

A medical ventilator Such displays Must be custom

Chart Junk (ducks) Tufte or Effective Communication 1990 2000 2010 1990 2000 2010

A Duck? (Tufte)

The concrete/abstraction tradeoff Object displays may lead to lower errors Lend themselves to overly literal interpretation. They are not general purpose. Object displays must be custom designed More abstract representations leave more room for interpretation (better support the creative process)

2 ½ D design Use 3D objects to represent entities Layout to make structure clear in 2D. -Connections, basic shapes Use canonical views

Holding attention -Object scene conflict Used in advertising

Emotional and motivational effects

Conclusion There is a great future in 3D object icons and object structures It is happening anyway, but nice to know that it is not always “chart junk”.

Conclusions Visual space is non-homogenous The plane orthogonal to the line of sight and the forward direction are very different. A 21/2D design attitude recognizes the cost of actions.

3D versus 2D 11.4% errors 3.7 sec sub-structure 21% errors 5.1 sec 20% memory errors 34% memory errors