Experiments show that knowledge-aligned SFT can reduce factual hallucinations on WildHalu and Biography while largely preserving general capabilities and confirm that SFT targets beyond the base model's knowledge drive hallucination behavior.
Abstract
Supervised fine-tuning (SFT) trains a base language model to imitate target responses, and these targets may require knowledge the base model has not robustly internalized. We study this as a source of hallucinations and frame a group of mitigation methods as \emph{knowledge-aligned SFT}: constraining SFT training targets to the base model's parametric knowledge. Under a unified setup, we compare existing generation-based and estimation-based knowledge-alignment methods and introduce two new variants: Evidence Rewrite, which verifies base-model generations using external evidence, and Recall Rewrite, which retains claims only when they can be consistently recalled by the base model. Experiments with Qwen 3 4B and OLMo 3 7B show that knowledge-aligned SFT can reduce factual hallucinations on WildHalu and Biography while largely preserving general capabilities. Recall Rewrite yields the strongest factuality gains and improves refusal behavior on UnknownBench. It thereby confirms that SFT targets beyond the base model's knowledge drive hallucination behavior.
To disentangle visual evidence at both semantic and spatial levels, ProtoLIP is introduced, a lightweight prototype-mediated evidence layer that organizes reusable visual prototypes into text-derived semantic families and uses coarse-to-fine evidence routing, where semantic families constrain prototype eligibility and...
Yan Zhu, Yong-Bo Chen, Zheng-Ming Ding et al.· 0 citations
RAG has become the de facto method for incorporating new, corpus-specific knowledge into an instruction following LLM (Instruct LLM). Although RAG-based prompting improves factual grounding, it fails when retrieval is incorrect or incomplete, leading to hallucinations. Finetuning methods such as RAFT and PA-RAG enhance...
Kushagra Bhushan, Meghanadh Pulivarthi, Sai Krishna Reddy Sathi et al.· 1 citation
Modern VLMs already encode much of what is needed for specialized domains; the challenge is learning how to ask, suggests modern VLMs already encode much of what is needed for specialized domains; the challenge is learning how to ask.
Gautam Rajendrakumar Gare, Si-Ying Li, He-Wei Wang et al.· 1 citation
The results show that fact transfer is very limited: under the strictest removal condition, a large majority of English-acquired facts fail to transfer into Persian, and it is shown that sentence-level co-occurrence removal is insufficient to eliminate fact signal.
Romina Oji, Marc Braun, Marcel Bollmann et al.· 0 citations
Refusal-Calibrated Group Relative Policy Optimization (RC-GRPO) is proposed, a calibrated RL strategy that strengthens the refusal ability of MLLMs while preserving localization performance, and enforces"None" outputs in rollouts for valid advantage estimation on negative samples and applies a penalty to prevent over-r...
Xuzheng Yang, Jun Ling, Tao Huang et al.· 1 citation
How faithfulness of LLMs to provided context depends on how plausible they perceive the context to be (context-memory conflict) is analyzed, which makes use of the increased difficulty of non-English and low-resource language text generation and input data based on local knowledge.
Peter Kochelka, Aleš Manuel Papáček, Vojtěch Dvořák et al.· 0 citations
Related blog posts
MIT News · Artificial Intelligence· news.mit.eduOct 13, 2026
Machine-learning networks can learn without detailed instructions from a designer. Those that do may offer insight into how the brain reorganizes itself during learning.
MIT News · Artificial Intelligence· news.mit.eduSep 29, 2026
Professor Sherry Turkle’s new book, “Artificial Intimacy,” offers a withering critique of chatbots and the antisocial dynamics she believes they encourage.