{"abstract":"Hold time consumes part of the decay ramp.","category":"Learning rate schedules","checks":6,"contract":"Hold base through hold_steps, then linearly decay to zero over decay_steps.","contract_signature":"step, base, hold_steps, decay_steps","evaluation_group":"lr-schedule-hold-then-decay","failed_approach":"Adding one to decay duration prevents reaching zero at the scheduled endpoint.","family":"w3-learning-rate-schedules-hold-then-decay","id":"FA-99106","implementations":{"attempt":{"sha256":"6d2b45531237f1ebd82a506cd6853ba627317d3f50470d33e7269f1b7f647a2e","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(step, base, hold_steps, decay_steps):\n    return base if step<=hold_steps else base*max(0,1-(step-hold_steps)/(decay_steps+1))\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('hold',solve(1,10,2,4),10); check('boundary',solve(2,10,2,4),10); check('first decay',solve(3,10,2,4),7.5); check('middle',solve(4,10,2,4),5); check('end',solve(6,10,2,4),0); check('after',solve(7,10,2,4),0)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"e8bb9f205de9d5b4c264bcf0459eab165a5a00f029ab8ca9cb6b20c593d8458d","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(step, base, hold_steps, decay_steps):\n    return base if step<hold_steps else base*max(0,1-step/decay_steps)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('hold',solve(1,10,2,4),10); check('boundary',solve(2,10,2,4),10); check('first decay',solve(3,10,2,4),7.5); check('middle',solve(4,10,2,4),5); check('end',solve(6,10,2,4),0); check('after',solve(7,10,2,4),0)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"These are toy scalar contracts with integer steps and finite parameters; they do not model framework defaults or optimizer state. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"w3-learning-rate-schedules-hold-then-decay","generated_at":"2026-09-30T16:48:20.352092+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic scalar schedule makes step-to-rate mapping explicit for a small training loop.","root_cause":"The decay fraction uses absolute step and therefore includes the preceding hold period.","sha256":"4b35e906815360d2b10d37fafddf53a04ae16e90a0f800fca9c159af797c9c61","title":"Hold time consumes part of the decay ramp · case 01","variant":1,"variant_policy":"The same explicitly authored fixtures repeat across all five numbered records; runtime N is unused. These records share one mechanism and must remain together in evaluation splits.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":27.488,"exit_code":1,"observations":[{"actual":10,"check":"hold","expected":10,"passed":true},{"actual":10,"check":"boundary","expected":10,"passed":true},{"actual":8.0,"check":"first decay","expected":7.5,"passed":false},{"actual":6.0,"check":"middle","expected":5,"passed":false},{"actual":1.9999999999999996,"check":"end","expected":0,"passed":false},{"actual":0,"check":"after","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"hold\", \"actual\": 10, \"expected\": 10, \"passed\": true}, {\"check\": \"boundary\", \"actual\": 10, \"expected\": 10, \"passed\": true}, {\"check\": \"first decay\", \"actual\": 8.0, \"expected\": 7.5, \"passed\": false}, {\"check\": \"middle\", \"actual\": 6.0, \"expected\": 5, \"passed\": false}, {\"check\": \"end\", \"actual\": 1.9999999999999996, \"expected\": 0, \"passed\": false}, {\"check\": \"after\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":27.112,"exit_code":1,"observations":[{"actual":10,"check":"hold","expected":10,"passed":true},{"actual":5.0,"check":"boundary","expected":10,"passed":false},{"actual":2.5,"check":"first decay","expected":7.5,"passed":false},{"actual":0,"check":"middle","expected":5,"passed":false},{"actual":0,"check":"end","expected":0,"passed":true},{"actual":0,"check":"after","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"hold\", \"actual\": 10, \"expected\": 10, \"passed\": true}, {\"check\": \"boundary\", \"actual\": 5.0, \"expected\": 10, \"passed\": false}, {\"check\": \"first decay\", \"actual\": 2.5, \"expected\": 7.5, \"passed\": false}, {\"check\": \"middle\", \"actual\": 0, \"expected\": 5, \"passed\": false}, {\"check\": \"end\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"after\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}