[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"branding":3,"analytics":7,"article-why-flat-loss-landscapes-fail-to-pick-the-best-model":10,"sections":34},{"siteName":4,"siteTagline":5,"publisherName":4,"contactEmail":6},"The Revision","Tech news, decoded.","editor@therevision.news",{"gaMeasurementId":8,"adsenseClientId":9},"G-ZW2MV82GYR","ca-pub-8533917693782264",{"article":11},{"id":12,"slug":13,"title":14,"dek":15,"body_md":16,"tags_json":17,"published_at":18,"created_at":19,"updated_at":20,"status":21,"review_note":22,"review_notes":23,"image_url":22,"persona_id":22,"persona_name":22,"section":24,"tags":25,"sources":29,"feedback":33,"feedback_at":22,"cost_usd":33,"total_tokens":33},9116,"why-flat-loss-landscapes-fail-to-pick-the-best-model","Why Flat Loss Landscapes Fail to Pick the Best Model","A new study shows curvature-based scores that predict a model's generalization gap still fail to flag the best model for deployment.","A new study finds that knowing how well a model will generalize doesn't tell you which model to actually deploy.\n\nResearchers tested whether a model's internal geometry, including a novel forward-only proxy tied to the Hessian and more familiar measures like Hessian trace and top-eigenvalue, could replace validation data for picking a trained network to deploy in computational biology. They ran the test across molecular property, protein fitness, and drug-response tasks, the kind of settings where real-world deployment often drifts away from the data a model was validated on. The team expected geometry-based scores to become more useful as standard validation correlation broke down, but that is not what happened. Instead, the new proxy kept tracking the size of a model's generalization gap on most tasks even when the established Hessian measures gave weak or contradicted signals.\n\nThe catch: a score that correctly predicts the size of a generalization gap can still fail to point at the best-performing model among several candidates, because curvature bounds don't reliably preserve the ranking between models. In some cases the flattest-looking model was a collapsed predictor, one that minimized error by hedging toward a safe, uninformative answer rather than actually fitting the data well. That distinction matters for biology labs leaning on these models to rank drug candidates or protein variants in settings where real validation data is scarce or mismatched to deployment conditions.\n\nAugmenting validation sets helped under some distribution shifts in the study and significantly hurt others, so there's no tidy substitute on offer here, geometry included.","[\"ai\",\"machine-learning\",\"computational-biology\",\"model-selection\"]","2026-10-01T04:00:00.000Z","2026-10-01T20:49:06.704Z","2026-10-01T20:49:09.653Z","published",null,[],"ai",[24,26,27,28],"machine-learning","computational-biology","model-selection",[30],{"name":31,"url":32},"arXiv cs.AI","https:\u002F\u002Farxiv.org\u002Fabs\u002F2609.39099",0,{"sections":35},[36,39,43,47,52,57,61,66,71,75,80,85,90,95],{"name":37,"slug":24,"count":38,"latest_published_at":18},"AI",5572,{"name":40,"slug":41,"count":42,"latest_published_at":18},"Security","security",815,{"name":44,"slug":45,"count":46,"latest_published_at":18},"Policy","policy",430,{"name":48,"slug":49,"count":50,"latest_published_at":51},"Deals","deals",298,"2026-09-30T21:00:26.000Z",{"name":53,"slug":54,"count":55,"latest_published_at":56},"Hardware","hardware",196,"2026-09-30T13:00:00.000Z",{"name":58,"slug":59,"count":60,"latest_published_at":18},"Science","science",163,{"name":62,"slug":63,"count":64,"latest_published_at":65},"Consumer Tech","consumer-tech",149,"2026-09-30T22:57:11.000Z",{"name":67,"slug":68,"count":69,"latest_published_at":70},"Dev Tools","dev-tools",93,"2026-10-01T02:30:48.000Z",{"name":72,"slug":73,"count":69,"latest_published_at":74},"Software","software","2026-09-30T21:41:11.000Z",{"name":76,"slug":77,"count":78,"latest_published_at":79},"Startups","startups",84,"2026-09-30T20:39:09.000Z",{"name":81,"slug":82,"count":83,"latest_published_at":84},"Gaming","gaming",51,"2026-09-30T16:24:30.000Z",{"name":86,"slug":87,"count":88,"latest_published_at":89},"General","general",50,"2026-09-30T21:37:54.000Z",{"name":91,"slug":92,"count":93,"latest_published_at":94},"Reviews","reviews",31,"2026-09-28T14:31:34.000Z",{"name":96,"slug":97,"count":98,"latest_published_at":99},"How-To","how-to",6,"2026-06-16T09:00:00.000Z"]