{"abstract":"Opponent tiebreak drops repeat encounters.","category":"Tournament pairing rules","checks":6,"contract":"Synthetic model: Sum the final integer score of each opponent occurrence; repeats and negative penalty-adjusted scores count.","evaluation_group":"tournament-encounter-score-contribution","failed_approach":"Keeping occurrences but suppressing negative penalty-adjusted scores changes the sum.","family":"z-tournament_pairing-buchholz-occurrences","id":"FA-12801","implementations":{"attempt":{"sha256":"b520d86d7ca53cc1d1037bec9eedc360e733866d273640e73177e6493776e6ba","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(opponents, scores):\n    return sum(scores[x] for x in opponents if scores[x]>0)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('repeat encounter', solve(['a','a'], {'a':N}), 2*N)\ncheck('penalty score', solve(['a'], {'a':-N}), -N)\ncheck('empty', solve([], {}), 0)\ncheck('zero', solve(['a'], {'a':0}), 0)\ncheck('mixed', solve(['a','b','a'], {'a':N,'b':2}), 2*N+2)\ncheck('cancel', solve(['a','b'], {'a':N,'b':-N}), 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":"1c1aaf31da0aa50f44eb24c2258328789690035c8bcd7e0da25afaa12df4daa9","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(opponents, scores):\n    return sum(scores[x] for x in set(opponents))\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('repeat encounter', solve(['a','a'], {'a':N}), 2*N)\ncheck('penalty score', solve(['a'], {'a':-N}), -N)\ncheck('empty', solve([], {}), 0)\ncheck('zero', solve(['a'], {'a':0}), 0)\ncheck('mixed', solve(['a','b','a'], {'a':N,'b':2}), 2*N+2)\ncheck('cancel', solve(['a','b'], {'a':N,'b':-N}), 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"},"fixed":{"sha256":"b3cd0ffefbaaa97a9ce78a1bae43922ad77d9c420647c85d9b89d67d97509be3","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(opponents, scores):\n    return sum(scores[x] for x in opponents)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('repeat encounter', solve(['a','a'], {'a':N}), 2*N)\ncheck('penalty score', solve(['a'], {'a':-N}), -N)\ncheck('empty', solve([], {}), 0)\ncheck('zero', solve(['a'], {'a':0}), 0)\ncheck('mixed', solve(['a','b','a'], {'a':N,'b':2}), 2*N+2)\ncheck('cancel', solve(['a','b'], {'a':N,'b':-N}), 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":"Controlled synthetic policy; does not implement an entire tournament system. 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-tournament_pairing-buchholz-occurrences","generated_at":"2026-09-29T14:39:00.169424+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Makes the stated pairing or standings policy executable without assuming any real federation rulebook.","repair":"Sum the final integer score of each opponent occurrence; repeats and negative penalty-adjusted scores count.","root_cause":"Opponent identifiers are deduplicated although every encounter contributes.","sha256":"610ad6dc69308c5123bfc48796a1007366ffb42637d85ae839477e0cc048ace0","title":"Opponent tiebreak drops repeat encounters · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":45.456,"exit_code":1,"observations":[{"actual":2,"check":"repeat encounter","expected":2,"passed":true},{"actual":0,"check":"penalty score","expected":-1,"passed":false},{"actual":0,"check":"empty","expected":0,"passed":true},{"actual":0,"check":"zero","expected":0,"passed":true},{"actual":4,"check":"mixed","expected":4,"passed":true},{"actual":1,"check":"cancel","expected":0,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"repeat encounter\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"penalty score\", \"actual\": 0, \"expected\": -1, \"passed\": false}, {\"check\": \"empty\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"zero\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"mixed\", \"actual\": 4, \"expected\": 4, \"passed\": true}, {\"check\": \"cancel\", \"actual\": 1, \"expected\": 0, \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.595,"exit_code":1,"observations":[{"actual":1,"check":"repeat encounter","expected":2,"passed":false},{"actual":-1,"check":"penalty score","expected":-1,"passed":true},{"actual":0,"check":"empty","expected":0,"passed":true},{"actual":0,"check":"zero","expected":0,"passed":true},{"actual":3,"check":"mixed","expected":4,"passed":false},{"actual":0,"check":"cancel","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"repeat encounter\", \"actual\": 1, \"expected\": 2, \"passed\": false}, {\"check\": \"penalty score\", \"actual\": -1, \"expected\": -1, \"passed\": true}, {\"check\": \"empty\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"zero\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"mixed\", \"actual\": 3, \"expected\": 4, \"passed\": false}, {\"check\": \"cancel\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":42.045,"exit_code":0,"observations":[{"actual":2,"check":"repeat encounter","expected":2,"passed":true},{"actual":-1,"check":"penalty score","expected":-1,"passed":true},{"actual":0,"check":"empty","expected":0,"passed":true},{"actual":0,"check":"zero","expected":0,"passed":true},{"actual":4,"check":"mixed","expected":4,"passed":true},{"actual":0,"check":"cancel","expected":0,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"repeat encounter\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"penalty score\", \"actual\": -1, \"expected\": -1, \"passed\": true}, {\"check\": \"empty\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"zero\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"mixed\", \"actual\": 4, \"expected\": 4, \"passed\": true}, {\"check\": \"cancel\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}