{"abstract":"Carryover correction skips an intervening wash injection.","category":"Laboratory measurement reporting","checks":7,"contract":"For chronological [kind,raw] injections, subtract one tenth of the preceding raw injection from sample signals. First predecessor is zero. Washes emit nothing but update predecessor. Return Fraction strings; kinds sample or wash.","contract_signature":"injections","evaluation_group":"model-2052cff16850063c","failed_approach":"Resetting predecessor to zero for a wash ignores its measured residual signal.","family":"z-laboratory_units-carryover-sequence","id":"FA-12426","implementations":{"attempt":{"sha256":"c85246d601194aa58cfe82145010670fa57a5c6840556bc030ae8e58d0f2ee74","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nfrom fractions import Fraction\nN = 1\nobservations = []\ndef solve(injections):\n    previous=0\n    out=[]\n    for kind,raw in injections:\n        if kind == 'sample':\n            out.append(str(Fraction(raw)-Fraction(previous,10)))\n            previous=raw\n        else:\n            previous=0\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('wash residual becomes predecessor', solve([('sample',100*N),('wash',10*N),('sample',20*N)]), [str(100*N),str(19*N)])\ncheck('wash first', solve([('wash',10*N),('sample',20*N)]), [str(19*N)])\ncheck('consecutive samples', solve([('sample',10*N),('sample',20*N)]), [str(10*N),str(19*N)])\ncheck('last of multiple washes', solve([('wash',100*N),('wash',10*N),('sample',20*N)]), [str(19*N)])\ncheck('only wash emits no report', solve([('wash',10*N)]), [])\ncheck('empty run', solve([]), [])\ncheck('first sample uncorrected', solve([('sample',N)]), [str(N)])\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":"b825d46ad240c9de65c08716c00f47ff48798f81b06ff31b9b313248f98a1bc1","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nfrom fractions import Fraction\nN = 1\nobservations = []\ndef solve(injections):\n    previous=0\n    out=[]\n    for kind,raw in injections:\n        if kind == 'sample':\n            out.append(str(Fraction(raw)-Fraction(previous,10)))\n            previous=raw\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('wash residual becomes predecessor', solve([('sample',100*N),('wash',10*N),('sample',20*N)]), [str(100*N),str(19*N)])\ncheck('wash first', solve([('wash',10*N),('sample',20*N)]), [str(19*N)])\ncheck('consecutive samples', solve([('sample',10*N),('sample',20*N)]), [str(10*N),str(19*N)])\ncheck('last of multiple washes', solve([('wash',100*N),('wash',10*N),('sample',20*N)]), [str(19*N)])\ncheck('only wash emits no report', solve([('wash',10*N)]), [])\ncheck('empty run', solve([]), [])\ncheck('first sample uncorrected', solve([('sample',N)]), [str(N)])\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":"Synthetic integer/rational fixtures only; no instrument validation or clinical interpretation. 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":"z-laboratory_units-carryover-sequence","generated_at":"2026-09-29T14:38:56.824393+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic synthetic laboratory reporting model isolates a software metadata contract; it is not a clinical procedure.","root_cause":"The previous sample is used instead of the previous physical injection.","sha256":"5bcb0d89b2d414bd0dcc0edb7737bd0ea2632e46e60cfddef97162ca60f6d6ea","title":"Carryover correction skips an intervening wash injection · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":41.865,"exit_code":1,"observations":[{"actual":["100","20"],"check":"wash residual becomes predecessor","expected":["100","19"],"passed":false},{"actual":["20"],"check":"wash first","expected":["19"],"passed":false},{"actual":["10","19"],"check":"consecutive samples","expected":["10","19"],"passed":true},{"actual":["20"],"check":"last of multiple washes","expected":["19"],"passed":false},{"actual":[],"check":"only wash emits no report","expected":[],"passed":true},{"actual":[],"check":"empty run","expected":[],"passed":true},{"actual":["1"],"check":"first sample uncorrected","expected":["1"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"wash residual becomes predecessor\", \"actual\": [\"100\", \"20\"], \"expected\": [\"100\", \"19\"], \"passed\": false}, {\"check\": \"wash first\", \"actual\": [\"20\"], \"expected\": [\"19\"], \"passed\": false}, {\"check\": \"consecutive samples\", \"actual\": [\"10\", \"19\"], \"expected\": [\"10\", \"19\"], \"passed\": true}, {\"check\": \"last of multiple washes\", \"actual\": [\"20\"], \"expected\": [\"19\"], \"passed\": false}, {\"check\": \"only wash emits no report\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"empty run\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"first sample uncorrected\", \"actual\": [\"1\"], \"expected\": [\"1\"], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.301,"exit_code":1,"observations":[{"actual":["100","10"],"check":"wash residual becomes predecessor","expected":["100","19"],"passed":false},{"actual":["20"],"check":"wash first","expected":["19"],"passed":false},{"actual":["10","19"],"check":"consecutive samples","expected":["10","19"],"passed":true},{"actual":["20"],"check":"last of multiple washes","expected":["19"],"passed":false},{"actual":[],"check":"only wash emits no report","expected":[],"passed":true},{"actual":[],"check":"empty run","expected":[],"passed":true},{"actual":["1"],"check":"first sample uncorrected","expected":["1"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"wash residual becomes predecessor\", \"actual\": [\"100\", \"10\"], \"expected\": [\"100\", \"19\"], \"passed\": false}, {\"check\": \"wash first\", \"actual\": [\"20\"], \"expected\": [\"19\"], \"passed\": false}, {\"check\": \"consecutive samples\", \"actual\": [\"10\", \"19\"], \"expected\": [\"10\", \"19\"], \"passed\": true}, {\"check\": \"last of multiple washes\", \"actual\": [\"20\"], \"expected\": [\"19\"], \"passed\": false}, {\"check\": \"only wash emits no report\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"empty run\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"first sample uncorrected\", \"actual\": [\"1\"], \"expected\": [\"1\"], \"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."}}