Skald: Minstrel Reconstructed

Scott Turner's Minstrel is considered a landmark story-generation system, cited as an important system in our field's history for the quality of its output. Other influential systems such as Meehan's Tale-Spin have inspired modern successors, but although a few systems have followed Minstrel's case-based approach, none of them use its “imaginative recall” technique. This paper details Skald, a publicly-released rational reconstruction of Minstrel that enables exploration of Turner's work and discovery of new implications for future research. A key finding is a brittleness only hinted at in Turner's publications: the story library, story templates, and the recall system must be tailored to one another for Turner's original system to function. We show that this can be ameliorated through a number of techniques, however, from adding differential costs to transformations to removing the least-successful author-level actions. Another key finding is that Turner's original “boredom” system limited leverage of the story library. An alternative and its results are presented here. What emerges from this work is a different picture of the original Minstrel than that currently present in the literature, as well as a new system, Skald, that sets the stage for future research to explore Turner's ideas for story generation.