A Provenance-First Discovery Layer for Research Gaps, Limitations, and Future Directions in ETDs

Abstract

Electronic theses and dissertations (ETDs) often state research gaps, limitations, and directions for future work. These statements can support literature review and research planning, but they are difficult to find in long, structurally varied documents. We present a provenance-first pipeline that turns such statements into source-linked records. A replaceable proposal model reads bounded source windows and returns a proposed statement type, a short synopsis, and a verbatim source passage. A deterministic aligner then locates that passage in the compiled text and records its physical PDF page or page span. The record contract stores source-derived fields separately from the interpretive overlay, so type, synopsis, and rhetorical ownership can change without altering the evidence address. Three questions structure the evaluation. A development study across bundled input configurations compares LLM extraction from structure-selected regions, model-selected chapters, whole-thesis and per-chapter inputs, and bounded sentence-numbered windows, including additional sampling and recovery passes. It also compares cue-based and supervised sentence-classification baselines. Single-pass bounded windows provide the best recall–precision balance in the directly comparable panels and become the fixed input interface. Deterministic alignment then locates 93.9% of proposed passages and excludes unresolved proposals before serialization. In the main-evaluation portion of a stratified record audit, 99.5% of records point to the exact physical PDF page; proposed-type mismatches are concentrated at the gap–limitation boundary. Under the fixed input and provenance contract, four 4B-class open-weight backends adapted only on 27B proposal outputs retain 90.3–92.1% of the selective 27B configuration’s reference-set coverage, have precision estimates 2.8–3.8 percentage points higher, and emit fewer passages per ETD. Distilling the precision filter into a second 4B model yields 81.7% audit-only precision at 71.4% reference-set coverage, showing that both the proposal and filtering stages can use 4B-class models. The resulting system is a source-linked discovery and review layer over ETD collections. The release contains prompts, schemas, run manifests, source-linked ledgers, and audit decisions.