{"abstract":"Short trips show a range whose low end equals the high end.","category":"Ride-hailing fare and surge pricing","checks":7,"contract":"Show a fare range from a point estimate in cents: low = 90% of the estimate floored to whole dollars, but never below the minimum fare; high = 110% of the estimate rounded up to whole dollars; if the range is narrower than 2.00 the high end becomes low + 2.00. Return [low, high] cents.","evaluation_group":"w2-ride-hailing-fare-surge-estimate-range","failed_approach":"Also clamping the high end still leaves a zero-width range.","family":"w2-ride-hailing-fare-surge-estimate-range-minimum-clamp-ordering","id":"FA-85696","implementations":{"attempt":{"sha256":"baf6ab101d8eccf9cc66f8cbc6ac6739ecdadd585c75fce6886b29f5d1b25197","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(est, minimum):\n    low = est * 9 // 10 // 100 * 100\n    high = -(-(est * 11) // 1000) * 100\n    if high - low < 200:\n        high = low + 200\n    low = max(low, minimum)\n    high = max(high, minimum)\n    return [low, high]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[('regression: minimum clamp ordering', [699, 800], [800, 1000]),\n  ('partial repair probe: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('second regression', [700, 1000], [1000, 1200]), ('normal control 1', [2500, 500], [2200, 2800]),\n  ('normal control 2', [1999, 500], [1700, 2200]), ('normal control 3', [1234, 1000], [1100, 1400]),\n  ('normal control 4', [1111, 800], [900, 1300])],\n [('regression: minimum clamp ordering', [700, 800], [800, 1000]),\n  ('partial repair probe: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('second regression', [700, 1000], [1000, 1200]), ('normal control 1', [2050, 800], [1800, 2300]),\n  ('normal control 2', [2500, 800], [2200, 2800]), ('normal control 3', [1111, 800], [900, 1300]),\n  ('normal control 4', [1999, 1000], [1700, 2200])],\n [('regression: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('partial repair probe: minimum clamp ordering', [700, 1000], [1000, 1200]),\n  ('second regression', [700, 800], [800, 1000]), ('normal control 1', [1999, 500], [1700, 2200]),\n  ('normal control 2', [2050, 800], [1800, 2300]), ('normal control 3', [2405, 800], [2100, 2700]),\n  ('normal control 4', [2500, 1000], [2200, 2800])],\n [('regression: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('partial repair probe: minimum clamp ordering', [700, 800], [800, 1000]),\n  ('second regression', [594, 800], [800, 1000]), ('normal control 1', [1111, 800], [900, 1300]),\n  ('normal control 2', [1999, 800], [1700, 2200]), ('normal control 3', [2050, 500], [1800, 2300]),\n  ('normal control 4', [3986, 800], [3500, 4400])],\n [('regression: minimum clamp ordering', [700, 1000], [1000, 1200]),\n  ('partial repair probe: minimum clamp ordering', [701, 800], [800, 1000]),\n  ('second regression', [1000, 1000], [1000, 1200]), ('normal control 1', [2050, 500], [1800, 2300]),\n  ('normal control 2', [2050, 800], [1800, 2300]), ('normal control 3', [1999, 1000], [1700, 2200]),\n  ('normal control 4', [664, 500], [500, 800])]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\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":"ca3023f5add842ce051aabbcae9c096f782afa3687418dd1702573a8af6eea07","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(est, minimum):\n    low = est * 9 // 10 // 100 * 100\n    high = -(-(est * 11) // 1000) * 100\n    if high - low < 200:\n        high = low + 200\n    low = max(low, minimum)\n    return [low, high]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[('regression: minimum clamp ordering', [699, 800], [800, 1000]),\n  ('partial repair probe: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('second regression', [700, 1000], [1000, 1200]), ('normal control 1', [2500, 500], [2200, 2800]),\n  ('normal control 2', [1999, 500], [1700, 2200]), ('normal control 3', [1234, 1000], [1100, 1400]),\n  ('normal control 4', [1111, 800], [900, 1300])],\n [('regression: minimum clamp ordering', [700, 800], [800, 1000]),\n  ('partial repair probe: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('second regression', [700, 1000], [1000, 1200]), ('normal control 1', [2050, 800], [1800, 2300]),\n  ('normal control 2', [2500, 800], [2200, 2800]), ('normal control 3', [1111, 800], [900, 1300]),\n  ('normal control 4', [1999, 1000], [1700, 2200])],\n [('regression: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('partial repair probe: minimum clamp ordering', [700, 1000], [1000, 1200]),\n  ('second regression', [700, 800], [800, 1000]), ('normal control 1', [1999, 500], [1700, 2200]),\n  ('normal control 2', [2050, 800], [1800, 2300]), ('normal control 3', [2405, 800], [2100, 2700]),\n  ('normal control 4', [2500, 1000], [2200, 2800])],\n [('regression: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('partial repair probe: minimum clamp ordering', [700, 800], [800, 1000]),\n  ('second regression', [594, 800], [800, 1000]), ('normal control 1', [1111, 800], [900, 1300]),\n  ('normal control 2', [1999, 800], [1700, 2200]), ('normal control 3', [2050, 500], [1800, 2300]),\n  ('normal control 4', [3986, 800], [3500, 4400])],\n [('regression: minimum clamp ordering', [700, 1000], [1000, 1200]),\n  ('partial repair probe: minimum clamp ordering', [701, 800], [800, 1000]),\n  ('second regression', [1000, 1000], [1000, 1200]), ('normal control 1', [2050, 500], [1800, 2300]),\n  ('normal control 2', [2050, 800], [1800, 2300]), ('normal control 3', [1999, 1000], [1700, 2200]),\n  ('normal control 4', [664, 500], [500, 800])]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\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":"18cd2c7fa7cd6f87acd15aab8497e6fdd20cd26099ade96b3d4121ce39d6ab62","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(est, minimum):\n    low = max(est * 9 // 10 // 100 * 100, minimum)\n    high = -(-(est * 11) // 1000) * 100\n    if high - low < 200:\n        high = low + 200\n    return [low, high]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[('regression: minimum clamp ordering', [699, 800], [800, 1000]),\n  ('partial repair probe: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('second regression', [700, 1000], [1000, 1200]), ('normal control 1', [2500, 500], [2200, 2800]),\n  ('normal control 2', [1999, 500], [1700, 2200]), ('normal control 3', [1234, 1000], [1100, 1400]),\n  ('normal control 4', [1111, 800], [900, 1300])],\n [('regression: minimum clamp ordering', [700, 800], [800, 1000]),\n  ('partial repair probe: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('second regression', [700, 1000], [1000, 1200]), ('normal control 1', [2050, 800], [1800, 2300]),\n  ('normal control 2', [2500, 800], [2200, 2800]), ('normal control 3', [1111, 800], [900, 1300]),\n  ('normal control 4', [1999, 1000], [1700, 2200])],\n [('regression: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('partial repair probe: minimum clamp ordering', [700, 1000], [1000, 1200]),\n  ('second regression', [700, 800], [800, 1000]), ('normal control 1', [1999, 500], [1700, 2200]),\n  ('normal control 2', [2050, 800], [1800, 2300]), ('normal control 3', [2405, 800], [2100, 2700]),\n  ('normal control 4', [2500, 1000], [2200, 2800])],\n [('regression: minimum clamp ordering', [1000, 1000], [1000, 1200]),\n  ('partial repair probe: minimum clamp ordering', [700, 800], [800, 1000]),\n  ('second regression', [594, 800], [800, 1000]), ('normal control 1', [1111, 800], [900, 1300]),\n  ('normal control 2', [1999, 800], [1700, 2200]), ('normal control 3', [2050, 500], [1800, 2300]),\n  ('normal control 4', [3986, 800], [3500, 4400])],\n [('regression: minimum clamp ordering', [700, 1000], [1000, 1200]),\n  ('partial repair probe: minimum clamp ordering', [701, 800], [800, 1000]),\n  ('second regression', [1000, 1000], [1000, 1200]), ('normal control 1', [2050, 500], [1800, 2300]),\n  ('normal control 2', [2050, 800], [1800, 2300]), ('normal control 3', [1999, 1000], [1700, 2200]),\n  ('normal control 4', [664, 500], [500, 800])]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\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":"A deterministic toy pricing contract stipulated for this example; it does not reproduce the pricing of any real ride-hailing operator or regulator. 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":"w2-ride-hailing-fare-surge-estimate-range-minimum-clamp-ordering","generated_at":"2026-09-29T14:50:42.838453+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Ride-hailing prices are computed per trip at scale; ordering, unit and boundary slips become systematic over- or under-charging.","repair":"Clamp the low end to the minimum before enforcing the width.","root_cause":"The minimum clamp is applied after the width rule, so the range can collapse.","sha256":"ec8122df50d7d2749348dc13346197b6ebc54dde5247c84f9c44621cccd009ca","title":"Minimum fare applied after the width adjustment · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":43.756,"exit_code":1,"observations":[{"actual":[800,800],"check":"regression: minimum clamp ordering","expected":[800,1000],"passed":false},{"actual":[1000,1100],"check":"partial repair probe: minimum clamp ordering","expected":[1000,1200],"passed":false},{"actual":[1000,1000],"check":"second regression","expected":[1000,1200],"passed":false},{"actual":[2200,2800],"check":"normal control 1","expected":[2200,2800],"passed":true},{"actual":[1700,2200],"check":"normal control 2","expected":[1700,2200],"passed":true},{"actual":[1100,1400],"check":"normal control 3","expected":[1100,1400],"passed":true},{"actual":[900,1300],"check":"normal control 4","expected":[900,1300],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: minimum clamp ordering\", \"actual\": [800, 800], \"expected\": [800, 1000], \"passed\": false}, {\"check\": \"partial repair probe: minimum clamp ordering\", \"actual\": [1000, 1100], \"expected\": [1000, 1200], \"passed\": false}, {\"check\": \"second regression\", \"actual\": [1000, 1000], \"expected\": [1000, 1200], \"passed\": false}, {\"check\": \"normal control 1\", \"actual\": [2200, 2800], \"expected\": [2200, 2800], \"passed\": true}, {\"check\": \"normal control 2\", \"actual\": [1700, 2200], \"expected\": [1700, 2200], \"passed\": true}, {\"check\": \"normal control 3\", \"actual\": [1100, 1400], \"expected\": [1100, 1400], \"passed\": true}, {\"check\": \"normal control 4\", \"actual\": [900, 1300], \"expected\": [900, 1300], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.746,"exit_code":1,"observations":[{"actual":[800,800],"check":"regression: minimum clamp ordering","expected":[800,1000],"passed":false},{"actual":[1000,1100],"check":"partial repair probe: minimum clamp ordering","expected":[1000,1200],"passed":false},{"actual":[1000,800],"check":"second regression","expected":[1000,1200],"passed":false},{"actual":[2200,2800],"check":"normal control 1","expected":[2200,2800],"passed":true},{"actual":[1700,2200],"check":"normal control 2","expected":[1700,2200],"passed":true},{"actual":[1100,1400],"check":"normal control 3","expected":[1100,1400],"passed":true},{"actual":[900,1300],"check":"normal control 4","expected":[900,1300],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: minimum clamp ordering\", \"actual\": [800, 800], \"expected\": [800, 1000], \"passed\": false}, {\"check\": \"partial repair probe: minimum clamp ordering\", \"actual\": [1000, 1100], \"expected\": [1000, 1200], \"passed\": false}, {\"check\": \"second regression\", \"actual\": [1000, 800], \"expected\": [1000, 1200], \"passed\": false}, {\"check\": \"normal control 1\", \"actual\": [2200, 2800], \"expected\": [2200, 2800], \"passed\": true}, {\"check\": \"normal control 2\", \"actual\": [1700, 2200], \"expected\": [1700, 2200], \"passed\": true}, {\"check\": \"normal control 3\", \"actual\": [1100, 1400], \"expected\": [1100, 1400], \"passed\": true}, {\"check\": \"normal control 4\", \"actual\": [900, 1300], \"expected\": [900, 1300], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":39.067,"exit_code":0,"observations":[{"actual":[800,1000],"check":"regression: minimum clamp ordering","expected":[800,1000],"passed":true},{"actual":[1000,1200],"check":"partial repair probe: minimum clamp ordering","expected":[1000,1200],"passed":true},{"actual":[1000,1200],"check":"second regression","expected":[1000,1200],"passed":true},{"actual":[2200,2800],"check":"normal control 1","expected":[2200,2800],"passed":true},{"actual":[1700,2200],"check":"normal control 2","expected":[1700,2200],"passed":true},{"actual":[1100,1400],"check":"normal control 3","expected":[1100,1400],"passed":true},{"actual":[900,1300],"check":"normal control 4","expected":[900,1300],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: minimum clamp ordering\", \"actual\": [800, 1000], \"expected\": [800, 1000], \"passed\": true}, {\"check\": \"partial repair probe: minimum clamp ordering\", \"actual\": [1000, 1200], \"expected\": [1000, 1200], \"passed\": true}, {\"check\": \"second regression\", \"actual\": [1000, 1200], \"expected\": [1000, 1200], \"passed\": true}, {\"check\": \"normal control 1\", \"actual\": [2200, 2800], \"expected\": [2200, 2800], \"passed\": true}, {\"check\": \"normal control 2\", \"actual\": [1700, 2200], \"expected\": [1700, 2200], \"passed\": true}, {\"check\": \"normal control 3\", \"actual\": [1100, 1400], \"expected\": [1100, 1400], \"passed\": true}, {\"check\": \"normal control 4\", \"actual\": [900, 1300], \"expected\": [900, 1300], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}