Informatisches Kolloquium &
Kolloquium des Internationalen Graduiertenkollegs CINACS
“Cross-Modal Interactions in Natural and Artificial Cognitive Systems”

Montag, 2. April 2007

Ass.-Prof. Dr. Christof Körner
Arbeitsbereich Allgemeine Psychologie
Institut für Psychologie
Karl-Franzens-Universität Graz
Österreich

Search and Reasoning Processes in Graph Comprehension

I will report a series of experiments that test a simple comprehension model for hierarchical graphs. Such graphs (e.g. visualizations of computer file systems, family trees, organisation charts etc.) represent relations between objects or concepts. Graph nodes represent the objects (e.g. family members) and interconnecting lines represent the relations between the objects (e.g. parenthood). In a typical experiment a subject responds to an interpretive question ("Is person A a descendant of person B?") by reading the information from the graph. Eye movements are being recorded throughout. The presented model postulates that responding to such a question involves two stages devoted to search for the relevant objects and a separate reasoning stage. Data analysis is based on the number of fixations made in each stage. I will focus on two experiments that use the technique of saccade-contingent display changes. In these experiments we alter the relation between relevant objects in the graph to test whether this manipulation affects subjects' responses. The results support the proposed model. Our studies allow the derivation of some design criteria for drawing 'good' graphs.

Kontakt

Prof. Dr. Ch. Habel
Telefon: 2417