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arXiv · 2410.07708

Learning Tree Pattern Transformations

Daniel Neider·Leif Sabellek·Johannes Schmidt·Fabian Vehlken·Thomas Zeume
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Abstract

Explaining why and how a tree $t$ structurally differs from another tree $t^\star$ is a question that is encountered throughout computer science, including in understanding tree-structured data such as XML or JSON data. In this article, we explore how to learn explanations for structural differences between pairs of trees from sample data: suppose we are given a set $\{(t_1, t_1^\star),\dots, (t_n, t_n^\star)\}$ of pairs of labelled, ordered trees; is there a small set of rules that explains the structural differences between all pairs $(t_i, t_i^\star)$? This raises two research questions: (i) what is a good notion of "rule" in this context?; and (ii) how can sets of rules explaining a data set be learned algorithmically? We explore these questions from the perspective of database theory by (1) introducing a pattern-based specification language for tree transformations; (2) exploring the computational complexity of variants of the above algorithmic problem, e.g. showing NP-hardness for very restricted variants; and (3) discussing how to solve the problem for data from CS education research using SAT solvers.

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BibTeXRIS

Daniel Neider, Leif Sabellek, Johannes Schmidt, Fabian Vehlken, Thomas Zeume. 2024-10-10. Learning Tree Pattern Transformations. https://arxiv.org/abs/2410.07708

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