  Current research on automatic readability assessment (ARA) has focused on
improving the performance of models in high-resource languages such as English.
In this work, we introduce and release BasahaCorpus as part of an initiative
aimed at expanding available corpora and baseline models for readability
assessment in lower resource languages in the Philippines. We compiled a corpus
of short fictional narratives written in Hiligaynon, Minasbate, Karay-a, and
Rinconada -- languages belonging to the Central Philippine family tree subgroup
-- to train ARA models using surface-level, syllable-pattern, and n-gram
overlap features. We also propose a new hierarchical cross-lingual modeling
approach that takes advantage of a language's placement in the family tree to
increase the amount of available training data. Our study yields encouraging
results that support previous work showcasing the efficacy of cross-lingual
models in low-resource settings, as well as similarities in highly informative
linguistic features for mutually intelligible languages.
