IDEAS home Printed from https://ideas.repec.org/p/arx/papers/2607.17427.html

Abliteration Is Not a Scalpel: Off-Target Effects of Refusal Removal on Decision Disposition Across Model Families

Author

Listed:
  • Aleksander Fafu{l}a

Abstract

Abliteration - deleting a model's refusal direction from its weights - is the standard recipe behind popular "uncensored" open-weight models. We show the surgery is not clean. As a disposition probe we use 21,600 decisions under uncertainty - weekly up/down calls on 60 Warsaw Stock Exchange equities over 18 weeks, replayed through a frozen pipeline so the decision-layer model is the only variable. The task elicits no refusals at all, so any between-arm delta is pure side effect. Holding provenance constant (official BF16 checkpoints, a single abliteration author, an identical serving stack, one byte-identical frozen prompt), we compare base and abliterated arms of two Mixture-of-Experts families, Gemma-4-26B-A4B-it and Qwen3-30B-A3B-Instruct-2507. Three effects replicate across both families (weeks-clustered bootstrap CIs excluding zero): abliterated models are systematically more optimistic (+12.2 pp Gemma, +7.4 pp Qwen; the confirmed preregistered endpoint), justify themselves at greater length, and use fewer explicit uncertainty words in forced self-critiques (both exploratory). A fourth effect reverses sign: the same operation makes Gemma-abliterated less confident and Qwen-abliterated more (family CIs non-overlapping) - one weight surgery, opposite shifts in expressed confidence. Capability covariates rule out instruction-following degradation as the driver, and no arm shows economic skill: the apparent edge of abliterated arms is regime beta, not alpha. Our provenance audit also caught two independent contamination channels - a mismatched-quantizer pilot pair and a stale community chat template that silently mangled the rendered prompt - suggesting toolchain artifacts are the rule in studies of community-modified checkpoints. Whoever deploys an "uncensored" model as an agent is deploying a measurably different decision-maker, not the base model minus refusals.

Suggested Citation

  • Aleksander Fafu{l}a, 2026. "Abliteration Is Not a Scalpel: Off-Target Effects of Refusal Removal on Decision Disposition Across Model Families," Papers 2607.17427, arXiv.org.
  • Handle: RePEc:arx:papers:2607.17427
    as

    Download full text from publisher

    File URL: https://arxiv.org/pdf/2607.17427
    File Function: Latest version
    Download Restriction: no
    ---><---

    References listed on IDEAS

    as
    1. John J. Horton & Apostolos Filippas & Benjamin S. Manning, 2023. "Large Language Models as Simulated Economic Agents: What Can We Learn from Homo Silicus?," NBER Working Papers 31122, National Bureau of Economic Research, Inc.
    Full references (including those not matched with items on IDEAS)

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Polachek, Solomon & Romano, Kenneth & Tonguc, Ozlem, 2026. "Strategic Reasoning and Sensitivity to Stakes in the Dictator and Ultimatum Games: LLMs vs. Human Proposers," IZA Discussion Papers 18545, IZA Network @ LISER.
    2. Iñaki Aldasoro & Ajit Desai, 2025. "Money Talks: AI Agents for Cash Management in Payment Systems," Staff Working Papers 25-35, Bank of Canada.
    3. Joy Buchanan & Stephen Hill & Olga Shapoval, 2024. "ChatGPT Hallucinates Non-existent Citations: Evidence from Economics," The American Economist, Sage Publications, vol. 69(1), pages 80-87, March.
    4. Felipe A. Csaszar & Harsh Ketkar & Hyunjin Kim, 2024. "Artificial Intelligence and Strategic Decision-Making: Evidence from Entrepreneurs and Investors," Strategy Science, INFORMS, vol. 9(4), pages 322-345, December.
    5. Shenkman, E. & Parshakov, P. & Matkin , N., 2026. "Comparative analysis of large language models and human behavior in the Dictator Game," Journal of the New Economic Association, New Economic Association, vol. 71(2), pages 177-203.
    6. Kevin Leyton-Brown & Paul Milgrom & Neil Newman & Ilya Segal, 2024. "Artificial Intelligence and Market Design: Lessons Learned from Radio Spectrum Reallocation," NBER Chapters, in: New Directions in Market Design, pages 119-151, National Bureau of Economic Research, Inc.
    7. Manon Reusens & Sofie Goethals & David Martens, 2026. "LLM Consumer Behavior Theory: Foundations of a Novel Research Field," Papers 2606.18005, arXiv.org.
    8. Amin Izadyar, 2026. "AI and Exchange Rate Predictability," Papers 2608.00761, arXiv.org.
    9. C. Monica Capra & Thomas J. Kniesner, 2025. "Daniel Kahneman’s underappreciated last published paper: Empirical implications for benefit-cost analysis and a chat session discussion with bots," Journal of Risk and Uncertainty, Springer, vol. 71(1), pages 29-51, August.
    10. John R. Graham & Campbell R. Harvey & Manish Jha, 2026. "CFOs Meet LLMs," Papers 2606.13812, arXiv.org, revised Sep 2026.
    11. Erdem, Orhan & Ashok, Ragavi Pobbathi, 2026. "LLMs are not weird: Comparing AI and human financial decision-making," Journal of Behavioral and Experimental Economics (formerly The Journal of Socio-Economics), Elsevier, vol. 120(C).
    12. van Loon, Austin & Kanopka, Klint, 2026. "Using large language models as a source of human behavioral data in social science experiments," SocArXiv y74mu_v1, Center for Open Science.
    13. Hongshen Sun & Juanjuan Zhang, 2025. "From Model Choice to Model Belief: Establishing a New Measure for LLM-Based Research," Papers 2512.23184, arXiv.org.
    14. Kirshner, Samuel N., 2024. "GPT and CLT: The impact of ChatGPT's level of abstraction on consumer recommendations," Journal of Retailing and Consumer Services, Elsevier, vol. 76(C).
    15. Shu Wang & Zijun Yao & Shuhuai Zhang & Jianuo Gai & Tracy Xiao Liu & Songfa Zhong, 2025. "When Experimental Economics Meets Large Language Models: Evidence-based Tactics," Papers 2505.21371, arXiv.org, revised Jul 2025.
    16. Tianjia Dong & Nadav Kunievsky & James A. Evans, 2026. "Measuring Behavior Portability in Large Language Models," Papers 2606.22797, arXiv.org.
    17. Iñaki Aldasoro & Ajit Desai, 2025. "AI agents for cash management in payment systems," BIS Working Papers 1310, Bank for International Settlements.
    18. Koji Takahashi & Joon Suk Park, 2025. "Generative AI for Surveys on Payment Apps: AIs' View on Privacy and Technology," IMES Discussion Paper Series 25-E-13, Institute for Monetary and Economic Studies, Bank of Japan.
    19. Zengqing Wu & Run Peng & Xu Han & Shuyuan Zheng & Yixin Zhang & Chuan Xiao, 2023. "Smart Agent-Based Modeling: On the Use of Large Language Models in Computer Simulations," Papers 2311.06330, arXiv.org, revised Dec 2023.
    20. repec:osf:osfxxx:udz28_v1 is not listed on IDEAS
    21. Hui Chen & Antoine Didisheim & Mohammad & Pourmohammadi & Luciano Somoza & Hanqing Tian, 2025. "A Financial Brain Scan of the LLM," Papers 2508.21285, arXiv.org, revised Feb 2026.

    More about this item

    NEP fields

    This paper has been announced in the following NEP Reports:

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:arx:papers:2607.17427. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: arXiv administrators (email available below). General contact details of provider: https://arxiv.org/ .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.