Early-Layer LoRA Fine-Tuning for Cross-Lingual Lexical Alignment in Zero-Shot Translation of Low-Resource African Languages
Abstract
Abstract: Large Language Models (LLMs) have demonstrated remarkable capabilities, yet their performance in low-resource languages (LRLs), such as Swahili, often lags due to data scarcity and underrepresentation in pre-training. A key challenge is achieving robust cross-lingual lexical alignment, crucial for tasks like translation and cross-lingual information retrieval. This paper introduces Targeted Lexical Injection (TLI), a novel and efficient fine-tuning approach. We first demonstrate that Lugha-Llama-8B-wura, a Swahili-centric LLM, exhibits strong, near-perfect lexical alignment for Swahili-English
Research Question
Does early-layer LoRA fine-tuning improve cross-lingual lexical alignment more effectively than full-model fine-tuning for low-resource African languages in zero-shot translation tasks?
Verification Level
| Paper level | L2, Source-grounded claims | |
| Source-grounded claims | 9 | |
| Claim record source | parsed source sections |
Descriptive public verification status only; aggregate claim counts are public, but individual claim records are not exposed here.
Truth-Engine Gate Verdict
| Status | Falsified | |
| Gate | Gate 2 — Verification (formal proof or sandbox reproduction) | |
| Reason | [Gate 3 RED-TEAM FALSIFIED] avg_attack_score=7.4/10. COUNTEREXAMPLE_HUNTER(7.5):The formula reproduces a specific numerical claim (cosine similarity of 0.99998 ; CITATION_AUDITOR(7.2):The formula repro computes a single cosine similarity value but does not demonst; REPLICATION_ATTACKER(7.5):The verification record only shows a single numerical match with a high toleranc | |
| Evaluated | 2026-06-15T12:05:54.424928+00:00 |
A claim in this record was tested against Gate 2 and failed: a counterexample was found, a proof did not type-check, or a reproduction attempt did not match the reported results. Evidence for the failure is attached to this record. VERIFIED requires an attached reproducible artifact (Lean4 proof source, or repro script and results) before this status can be set; it is not derived from review score or claim count.
Quality Tier
| Tier | DOI grade | |
| Basis | Review score and verified-claim count meet DOI-grade public quality thresholds. |
Descriptive public triage only; this tier does not alter current publication or DOI behavior.
Quality Dimensions
| Evidence strength | MEDIUM | |
| Citation grounding | MEDIUM | |
| Uncertainty disclosure | MEDIUM | |
| Reproducibility status | HIGH |
Automated triage signals derived from public fields; not human peer review or independent validation.
Correction Record
| Status | CURRENT |
| Correction count | 0 |
| Manifest contract | paper-manifest-v1.1 |
| Correction contract | correction-record-v1 |
Public corrections are additive records. Current status does not claim the synthesis is error-free.
Provenance
| Publisher | Assignee Research |
| Public provenance | L4, External archival record |
| Report artifact | Available |
| External record | Registered |
| Claim lineage | 9 aggregate source-grounded claims |
| Review method | Automated multi-reviewer assessment |
| Quality guide | How to read scores, claims, manifests, and evidence links |
| Provenance contract | source-provenance-v1 |
| Note | Machine-generated synthesis of existing literature. Not primary research. |