Abstract Various known models of probabilistic XML can be represented as instantiations of the abstract notion of p-documents. In addition to ordinary nodes, p-documents have distributional nodes that specify the possible worlds and their probabilistic distribution. Particular families of p-documents are determined by the types of distributional nodes that can be used as well as by the structural constraints on the placement of those nodes in a p-document. Some of the resulting families provide natural extensions and combinations of previously studied probabilistic XML models. The focus of the paper is on the expressive power of families of p-documents. In particular, two main issues are studied. Some of the results described in this paper were reported in [1, 2] .
A unified view of existing probabilistic XML models, in the form of p-documents, has been proposed in REF .
On the expressiveness of probabilistic XML models
The VLDB Journal
The VLDB Journal
Computer Science