Narrative support for technical documents Formalising Rhetorical Structure Theory

1. Narrative support for technical documentsFormalising Rhetorical Structure Theory Professor Peter Henderson, Nishadi De Silva Declarative Systems and Software Engineering Research Group, School of Electronics and Computer Science, University of Southampton, UK.

2. Overview • Description of the problem • Introduction to narrative theories • Applying narrative theories to improve technical documents • Features of our software tool, Computer-Aided Narrative Support (CANS) • Outline for future work

3. The problem • Written communication is unavoidable • Effective written documents need to be well-structured and contain a coherent narrative - Technical writing • Many theories to enhance a narrative were developed in the past by linguists and researchers into narratives • However, existing writing tools do not support document narratives or incorporate these narrative theories

4. Narratives explained • What is a narrative? -A narrative is the…representation of a series of events meaningfully connected in a temporal and causal way [Onega & Landa, 1996] - Narrative ≈ Story • Narrative theories - Rhetorical Structure Theory (RST), 1988 - Simpler than most other theories - Can be used to enhance coherence, identify (un)necessary segments of text • The ‘story’ that a document conveys to the reader is called a ‘document narrative’

5. Rhetorical Structure Theory (RST) • Divide a piece of text into segments • A segment is either a nucleus (N) or a satellite (S) • Relationships exist between these text segments • Coherence is achieved by the overall effect created by a relation • A coherent narrative should form a tree of relationships (example coming up) Example:

6. Applying RST to a short story An instance of the generic narrative Generic narrative 3 1 [There is an initial condition.] 1 [Then a problem arises] 2 [that disrupts this condition.] 3 [A solution is sought. One of the solutions fixes the problem] 4 [and restores the initial condition.] 5 Fido is a happy dog. Last week Fido got fleas and started scratching. This made Fido unhappy. Noticing this, Fido’s owner took him to the vet. The vet recommended a flea treatment which got rid of the fleas. Fido stopped scratching and was happy again! RST tree for the generic narrative 2

7. Another Example: Generic Narrative for a Research Proposal [We want you to fund us]1 [because we will achieve these objectives/results.]2 ………………. [We know this problem is unsolved]7 [because we have studied the background.]8 [We will solve this problem]9 [by this method.]10 ……….. [The research will be carried out by these researchers]16 [and they are the most qualified to do this because justification-of-researchers.]17 ……….. (Generic narrative obtained after studying many suggested formats for Research Proposals from various sources.)

8. RST analysis of research proposal narrative Collapsed RST tree

9. CANS: Computer Aided Narrative Support • Allows a user to create a generic narrative for a document type and build a RST tree for it • Questions asked by the tool prompt an author for document content • Can explore alternative narratives • Tool can be used to ‘get story straight’ and create an outline that best suits the document’s purpose • Still very simple and needs more work!

10. Creating the generic narrative for a document User enters the structure for the document here (i.e. the document narrative)

11. Building the RST tree bottom-up <hypRelation id=“subtree-A“ type=“Motivation"> <satellite id=“5" /> <nucleus id=“4" /> </hypRelation>

12. Questions asked from the user Questions for the author. Each question preceded with a history of its relations to other segments. View the RST tree or the document narrative

13. Exploring alternative document narratives • Often necessary to present the same content in different ways (i.e. different document narratives) • Traverse the RST tree in different ways • Each traversal produces different narratives (some versions not grammatically sound!) Nucleus arranged according to relationship Nucleus first, Satellite second

14. Other features • Web-based • XSLT, JSP, HTML • XML database • RST structures stored using URML (Underspecified Rhetorical Markup Language) • List of predefined narrative structures provided in tool - Research Proposal - Abstract for a paper - Short Story - A short presentation • Can create different documents with same content List expected to grow…

15. Future work • Collaborative authoring, distributed documents • Generate questions automatically from RST tree • More ways to produce alternative narratives • Develop simplified version of RST more suited to technical documents • Incorporate RSTTool, Xindice, other narrative theories

16. Summary • Document narratives need to be coherent, well-structured and planned • Narrative theories can help achieve this • We have selectedRhetorical Structure Theory (RST) • CANS makes use of RST to help an author create and explore document narratives • Further improvements to this tool and future work directions were also outlined Thank you!