{"abstract":"ordinal labels are treated as numeric distances.","category":"Preference pair construction","checks":6,"contract":"Rows are [id,category]. Categories map low < middle < high. Return every strictly ordered [higher_id,lower_id] pair once in input pair order.","contract_signature":"rows","evaluation_group":"preference-ordinal-adjacent","failed_approach":"Comparing category strings lexically puts labels such as low and high in the wrong order.","family":"w3-preference-pair-construction-ordinal-adjacent","id":"FA-100106","implementations":{"attempt":{"sha256":"89db13e59671860807ead9a14898a8e032bd7c5058437338ffac493383a546c9","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(rows):\n    rank={\"low\":0,\"middle\":1,\"high\":2}\n    return [[a[0],b[0]] for i,a in enumerate(rows) for b in rows[i+1:] if rank[a[1]]-rank[b[1]]>=2]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\na='a'+str(N); b='b'+str(N)\ncheck('adjacent ordinal pair',solve([[a,'middle'],[b,'low']]),[[a,b]])\ncheck('reverse order',solve([['a','low'],['b','high']]),[['b','a']])\ncheck('tie skipped',solve([['a','middle'],['b','middle']]),[])\ncheck('empty',solve([]),[])\ncheck('full order',solve([['a','high'],['b','middle'],['c','low']]),[['a','b'],['a','c'],['b','c']])\ncheck('singleton',solve([['a','low']]),[])\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":"a97721fbf75699fe1a2bb6aa1ed92f117e9ce6e7597540f4ae0a3f9569c02347","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(rows):\n    return [[a[0],b[0]] for i,a in enumerate(rows) for b in rows[i+1:] if a[1]>b[1]]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\na='a'+str(N); b='b'+str(N)\ncheck('adjacent ordinal pair',solve([[a,'middle'],[b,'low']]),[[a,b]])\ncheck('reverse order',solve([['a','low'],['b','high']]),[['b','a']])\ncheck('tie skipped',solve([['a','middle'],['b','middle']]),[])\ncheck('empty',solve([]),[])\ncheck('full order',solve([['a','high'],['b','middle'],['c','low']]),[['a','b'],['a','c'],['b','c']])\ncheck('singleton',solve([['a','low']]),[])\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 explicit toy record contracts; they do not claim compatibility with a trainer or improved model behavior. 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-preference-pair-construction-ordinal-adjacent","generated_at":"2026-09-30T16:48:31.716945+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A small deterministic preference-data transform makes pair semantics inspectable without a training framework.","root_cause":"Ordinal categories establish order but not meaningful numeric distance.","sha256":"eee1b7e729cbd76f616f831ad043d3ac4fc9254673be50803dd6b1a603381a6a","title":"Preference pairs: ordinal labels are treated as numeric distances · case 01","variant":1,"variant_policy":"The fixture code references N, supplied as 1 through 5. Fixed boundary checks may repeat. These records share one mechanism and must remain together in evaluation splits.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":27.869,"exit_code":1,"observations":[{"actual":[],"check":"adjacent ordinal pair","expected":[["a1","b1"]],"passed":false},{"actual":[],"check":"reverse order","expected":[["b","a"]],"passed":false},{"actual":[],"check":"tie skipped","expected":[],"passed":true},{"actual":[],"check":"empty","expected":[],"passed":true},{"actual":[["a","c"]],"check":"full order","expected":[["a","b"],["a","c"],["b","c"]],"passed":false},{"actual":[],"check":"singleton","expected":[],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"adjacent ordinal pair\", \"actual\": [], \"expected\": [[\"a1\", \"b1\"]], \"passed\": false}, {\"check\": \"reverse order\", \"actual\": [], \"expected\": [[\"b\", \"a\"]], \"passed\": false}, {\"check\": \"tie skipped\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"empty\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"full order\", \"actual\": [[\"a\", \"c\"]], \"expected\": [[\"a\", \"b\"], [\"a\", \"c\"], [\"b\", \"c\"]], \"passed\": false}, {\"check\": \"singleton\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":27.868,"exit_code":1,"observations":[{"actual":[["a1","b1"]],"check":"adjacent ordinal pair","expected":[["a1","b1"]],"passed":true},{"actual":[["a","b"]],"check":"reverse order","expected":[["b","a"]],"passed":false},{"actual":[],"check":"tie skipped","expected":[],"passed":true},{"actual":[],"check":"empty","expected":[],"passed":true},{"actual":[["b","c"]],"check":"full order","expected":[["a","b"],["a","c"],["b","c"]],"passed":false},{"actual":[],"check":"singleton","expected":[],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"adjacent ordinal pair\", \"actual\": [[\"a1\", \"b1\"]], \"expected\": [[\"a1\", \"b1\"]], \"passed\": true}, {\"check\": \"reverse order\", \"actual\": [[\"a\", \"b\"]], \"expected\": [[\"b\", \"a\"]], \"passed\": false}, {\"check\": \"tie skipped\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"empty\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"full order\", \"actual\": [[\"b\", \"c\"]], \"expected\": [[\"a\", \"b\"], [\"a\", \"c\"], [\"b\", \"c\"]], \"passed\": false}, {\"check\": \"singleton\", \"actual\": [], \"expected\": [], \"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."}}