List of Figures

• General control flow of the new model
• The four different types of reversible grammar approaches which are discussed in this work.
• A summary of the approaches discussed in relationship to the new approach. The arrows indicate the relationship of most direct influence.
• The left dg directly mirrors the set of atomic constraints expressed in the example -constraint, and the right dg bears additional constraints. Hence, it is more informative than the left one.
• Some of the sub-dgs of the dg given in figure
• The relationship between paraphrases and ambiguities.
• The procedure for prediction.
• The procedure for passive-completion.
• The procedure for active-completion.
• The procedure for scanning.
• An agenda-based control mechanism.
• The procedure that adds new items to the table if they are not blocked.
• The procedure APPLY-TASK.
• A trace of parsing the string ``weil peter heute lügen erzählt.'' For explanations of the symbols used see text.
• The derivation tree of the example sentence. The labels of the node refer to the names of the rules of the grammar in Appendix A.
• A trace of generating from ``weil(heute(erzaehlen(peter,luegen)))''. For explanations of the symbols used see text.
• All possible derivation trees admitted by the grammar for the generation example.
• The relationship of generated items of the different inference rules.
• A trace through parsing of the string ``sieht Peter mit Maria''.
• A trace through generation of ``sehen(Peter,mit(Maria))''
• The item sharing approach using the uniform tabular algorithm. During the different modes the uniform algorithm maintains different agendas and private active items for the different modes. However, passive items are shared by both directions.
• The Architecture of an NLS using a reversible grammar.
• Levelt's perceptual loop theory of self-monitoring.
• Relationship between ambiguities and paraphrases.
• Schematic structure of an Anticipation Feedback Loop, based on Wahlster and Kobsa [1986].
• The Architecture of the new reversible system.
• Derivation trees
• Marked derivation tree
• Markers are pushed one level upward
• Derivation trees of the simple attachment example
• Marked tree of German example
• Markers are pushed one level upward