Diagrammatic Reasoning about Allen's Interval Relations. AAAI 1996 Spring Symposium Series: Reasoning with Diagrammatic Representations. Stanford University. 83--91. Schlieder, C. (in preparation). The construction of preferred mental models in reasoning

we explore different ways in which a computa-tional model of diagrammatic reasoning can cap-ture imagery experiences which subjects reported in an experiment on spatial reasoning. The algo-rithmic reconstruction of this particular reasoning process suggests that computational models of dia-grammatic reasoning should be formulated at dif-ferent levels of abstraction. Four levels are distinguished- ordinal positioning, metrical posi-tioning, pictorial merging and object depiction. Finally, consequences for the computational mod-elling of individual differences in imagery are dis-cussed.