FA-63216 / Insurance premium rating / Open access

Retrospective rating adjustment: Loss conversion factor is applied to the basic premium · case 01

Retro premiums are inflated because expense loading is converted like losses.

Verified by executionVariant 1 · 9 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The LCF multiplies basic premium plus losses.

THE FAILURE

The LCF multiplies basic premium plus losses.

Unsuccessful approach: Dropping the LCF altogether omits loss adjustment expense.

Case contract

Input standard premium, basic, lcf, tax (x1000), min and max (per mille of standard), loss_limit, claims (negative = recovery). max<min -> 'invalid bounds'. Limited losses = max(0, sum(min(claim, limit))). Retro = (standard*basic + limited*lcf)*tax, bounded by [standard*min, standard*max] (bounds already include tax), rounded half-up. Return [limited, retro].

Why this case matters

Retrospective plans settle premium after losses, so each conversion factor and bound has to sit at the right step.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import math
from fractions import Fraction
N = 1
observations = []
def solve(x):
    sp=x['standard']
    if x['max']<x['min']: return 'invalid bounds'
    lim=max(0,sum(min(c,x['loss_limit']) for c in x['claims']))
    basic=Fraction(sp*x['basic'],1000)
    retro=(basic+lim)*Fraction(x['lcf'],1000)*Fraction(x['tax'],1000)
    lo=Fraction(sp*x['min'],1000); hi=Fraction(sp*x['max'],1000)
    retro=max(lo,min(hi,retro))
    return [lim, math.floor(retro+Fraction(1,2))]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['moderate losses between bounds', {'standard': 1208187, 'basic': 250, 'lcf': 1100, 'tax': 1030, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [65251, 117766, 199866, 72604]}, [455487, 827175]], ['large claim limited', {'standard': 1536795, 'basic': 250, 'lcf': 1100, 'tax': 1050, 'min': 600, 'max': 3000, 'loss_limit': 5000000, 'claims': [7899385, 85219]}, [5085219, 4610385]], ['maximum binds', {'standard': 576969, 'basic': 250, 'lcf': 1100, 'tax': 1030, 'min': 500, 'max': 1200, 'loss_limit': 5000000, 'claims': [3887820, 3676391, 3519603, 3011895]}, [14095709, 692363]], ['no losses minimum binds', {'standard': 783317, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 500, 'max': 1400, 'loss_limit': 5000000, 'claims': []}, [0, 391659]], ['subrogation recovery offsets', {'standard': 1402360, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [299401, -71949]}, [227452, 581085]], ['net recovery floors at zero', {'standard': 1970882, 'basic': 200, 'lcf': 1150, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-13900]}, [0, 591265]], ['inverted bounds rejected', {'standard': 857821, 'basic': 200, 'lcf': 1150, 'tax': 1030, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 1032758, 'basic': 250, 'lcf': 1200, 'tax': 1030, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 929482]], ['near-minimum losses', {'standard': 1037917, 'basic': 250, 'lcf': 1200, 'tax': 1030, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [196003]}, [196003, 509523]]], [['moderate losses between bounds', {'standard': 559811, 'basic': 250, 'lcf': 1150, 'tax': 1030, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [168808, 170340, 188681, 153930]}, [681759, 951695]], ['large claim limited', {'standard': 1398667, 'basic': 200, 'lcf': 1150, 'tax': 1030, 'min': 500, 'max': 3000, 'loss_limit': 5000000, 'claims': [8563900, 72244]}, [5072244, 4196001]], ['maximum binds', {'standard': 1860838, 'basic': 250, 'lcf': 1100, 'tax': 1050, 'min': 600, 'max': 1200, 'loss_limit': 5000000, 'claims': [3974702, 2021857, 3323996, 2741110]}, [12061665, 2233006]], ['no losses minimum binds', {'standard': 1054836, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 500, 'max': 1400, 'loss_limit': 5000000, 'claims': []}, [0, 527418]], ['subrogation recovery offsets', {'standard': 572933, 'basic': 250, 'lcf': 1150, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [215865, -67794]}, [148071, 322920]], ['net recovery floors at zero', {'standard': 1415569, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-23951]}, [0, 424671]], ['inverted bounds rejected', {'standard': 1885857, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 1658903, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 1493013]], ['near-minimum losses', {'standard': 1831216, 'basic': 250, 'lcf': 1150, 'tax': 1030, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [255597]}, [255597, 824047]]], [['moderate losses between bounds', {'standard': 1953166, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [130486, 146045, 106267, 80838]}, [463636, 970005]], ['large claim limited', {'standard': 1375996, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 600, 'max': 3000, 'loss_limit': 5000000, 'claims': [8850428, 26063]}, [5026063, 4127988]], ['maximum binds', {'standard': 1822101, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 600, 'max': 1200, 'loss_limit': 5000000, 'claims': [3010425, 2467545, 2177771, 3447891]}, [11103632, 2186521]], ['no losses minimum binds', {'standard': 1516833, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 500, 'max': 1400, 'loss_limit': 5000000, 'claims': []}, [0, 758417]], ['subrogation recovery offsets', {'standard': 714829, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [292326, -101272]}, [191054, 370781]], ['net recovery floors at zero', {'standard': 1501098, 'basic': 200, 'lcf': 1100, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-22616]}, [0, 450329]], ['inverted bounds rejected', {'standard': 696781, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 802028, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 721825]], ['near-minimum losses', {'standard': 715359, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [161153]}, [161153, 346549]]], [['moderate losses between bounds', {'standard': 714988, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [147807, 50783, 101639, 147624]}, [447853, 714442]], ['large claim limited', {'standard': 1075364, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 600, 'max': 3000, 'loss_limit': 5000000, 'claims': [6621396, 51697]}, [5051697, 3226092]], ['maximum binds', {'standard': 636493, 'basic': 250, 'lcf': 1200, 'tax': 1050, 'min': 500, 'max': 1200, 'loss_limit': 5000000, 'claims': [3206066, 2811387, 2370852, 2596520]}, [10984825, 763792]], ['no losses minimum binds', {'standard': 1974481, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 500, 'max': 1600, 'loss_limit': 5000000, 'claims': []}, [0, 987241]], ['subrogation recovery offsets', {'standard': 1092045, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [210597, -95806]}, [114791, 366843]], ['net recovery floors at zero', {'standard': 1088467, 'basic': 250, 'lcf': 1200, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-13789]}, [0, 326540]], ['inverted bounds rejected', {'standard': 1508678, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 811592, 'basic': 250, 'lcf': 1200, 'tax': 1050, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 730433]], ['near-minimum losses', {'standard': 1513685, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [237641]}, [237641, 681158]]], [['moderate losses between bounds', {'standard': 1863348, 'basic': 250, 'lcf': 1200, 'tax': 1050, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [182396, 119506, 129126, 64521]}, [495549, 1113521]], ['large claim limited', {'standard': 1794820, 'basic': 200, 'lcf': 1100, 'tax': 1030, 'min': 500, 'max': 3000, 'loss_limit': 5000000, 'claims': [6997029, 30223]}, [5030223, 5384460]], ['maximum binds', {'standard': 1446879, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 500, 'max': 1200, 'loss_limit': 5000000, 'claims': [3226070, 2149089, 2381869, 2566788]}, [10323816, 1736255]], ['no losses minimum binds', {'standard': 1111989, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 500, 'max': 1400, 'loss_limit': 5000000, 'claims': []}, [0, 555995]], ['subrogation recovery offsets', {'standard': 930668, 'basic': 250, 'lcf': 1150, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [215001, -125166]}, [89835, 346057]], ['net recovery floors at zero', {'standard': 790663, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-24524]}, [0, 237199]], ['inverted bounds rejected', {'standard': 901935, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 802066, 'basic': 250, 'lcf': 1150, 'tax': 1050, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 721859]], ['near-minimum losses', {'standard': 1352189, 'basic': 250, 'lcf': 1150, 'tax': 1050, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [178467]}, [178467, 608485]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
moderate losses between bounds	`[455487, 858286]`	`[455487, 827175]`	Failed
large claim limited	`[5085219, 4610385]`	`[5085219, 4610385]`	Passed
maximum binds	`[14095709, 692363]`	`[14095709, 692363]`	Passed
no losses minimum binds	`[0, 391659]`	`[0, 391659]`	Passed
subrogation recovery offsets	`[227452, 639984]`	`[227452, 581085]`	Failed
net recovery floors at zero	`[0, 591265]`	`[0, 591265]`	Passed
inverted bounds rejected	`invalid bounds`	`invalid bounds`	Passed
flat plan with equal bounds	`[100000, 929482]`	`[100000, 929482]`	Passed
near-minimum losses	`[196003, 562976]`	`[196003, 509523]`	Failed

SHA-256 / ce53296d3d999d147de19d175e034dd0801d9e6c92b7f2e31ac0fc64081059bc

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import math
from fractions import Fraction
N = 1
observations = []
def solve(x):
    sp=x['standard']
    if x['max']<x['min']: return 'invalid bounds'
    lim=max(0,sum(min(c,x['loss_limit']) for c in x['claims']))
    basic=Fraction(sp*x['basic'],1000)
    retro=(basic+lim)*Fraction(x['tax'],1000)
    lo=Fraction(sp*x['min'],1000); hi=Fraction(sp*x['max'],1000)
    retro=max(lo,min(hi,retro))
    return [lim, math.floor(retro+Fraction(1,2))]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['moderate losses between bounds', {'standard': 1208187, 'basic': 250, 'lcf': 1100, 'tax': 1030, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [65251, 117766, 199866, 72604]}, [455487, 827175]], ['large claim limited', {'standard': 1536795, 'basic': 250, 'lcf': 1100, 'tax': 1050, 'min': 600, 'max': 3000, 'loss_limit': 5000000, 'claims': [7899385, 85219]}, [5085219, 4610385]], ['maximum binds', {'standard': 576969, 'basic': 250, 'lcf': 1100, 'tax': 1030, 'min': 500, 'max': 1200, 'loss_limit': 5000000, 'claims': [3887820, 3676391, 3519603, 3011895]}, [14095709, 692363]], ['no losses minimum binds', {'standard': 783317, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 500, 'max': 1400, 'loss_limit': 5000000, 'claims': []}, [0, 391659]], ['subrogation recovery offsets', {'standard': 1402360, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [299401, -71949]}, [227452, 581085]], ['net recovery floors at zero', {'standard': 1970882, 'basic': 200, 'lcf': 1150, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-13900]}, [0, 591265]], ['inverted bounds rejected', {'standard': 857821, 'basic': 200, 'lcf': 1150, 'tax': 1030, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 1032758, 'basic': 250, 'lcf': 1200, 'tax': 1030, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 929482]], ['near-minimum losses', {'standard': 1037917, 'basic': 250, 'lcf': 1200, 'tax': 1030, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [196003]}, [196003, 509523]]], [['moderate losses between bounds', {'standard': 559811, 'basic': 250, 'lcf': 1150, 'tax': 1030, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [168808, 170340, 188681, 153930]}, [681759, 951695]], ['large claim limited', {'standard': 1398667, 'basic': 200, 'lcf': 1150, 'tax': 1030, 'min': 500, 'max': 3000, 'loss_limit': 5000000, 'claims': [8563900, 72244]}, [5072244, 4196001]], ['maximum binds', {'standard': 1860838, 'basic': 250, 'lcf': 1100, 'tax': 1050, 'min': 600, 'max': 1200, 'loss_limit': 5000000, 'claims': [3974702, 2021857, 3323996, 2741110]}, [12061665, 2233006]], ['no losses minimum binds', {'standard': 1054836, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 500, 'max': 1400, 'loss_limit': 5000000, 'claims': []}, [0, 527418]], ['subrogation recovery offsets', {'standard': 572933, 'basic': 250, 'lcf': 1150, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [215865, -67794]}, [148071, 322920]], ['net recovery floors at zero', {'standard': 1415569, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-23951]}, [0, 424671]], ['inverted bounds rejected', {'standard': 1885857, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 1658903, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 1493013]], ['near-minimum losses', {'standard': 1831216, 'basic': 250, 'lcf': 1150, 'tax': 1030, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [255597]}, [255597, 824047]]], [['moderate losses between bounds', {'standard': 1953166, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [130486, 146045, 106267, 80838]}, [463636, 970005]], ['large claim limited', {'standard': 1375996, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 600, 'max': 3000, 'loss_limit': 5000000, 'claims': [8850428, 26063]}, [5026063, 4127988]], ['maximum binds', {'standard': 1822101, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 600, 'max': 1200, 'loss_limit': 5000000, 'claims': [3010425, 2467545, 2177771, 3447891]}, [11103632, 2186521]], ['no losses minimum binds', {'standard': 1516833, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 500, 'max': 1400, 'loss_limit': 5000000, 'claims': []}, [0, 758417]], ['subrogation recovery offsets', {'standard': 714829, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [292326, -101272]}, [191054, 370781]], ['net recovery floors at zero', {'standard': 1501098, 'basic': 200, 'lcf': 1100, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-22616]}, [0, 450329]], ['inverted bounds rejected', {'standard': 696781, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 802028, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 721825]], ['near-minimum losses', {'standard': 715359, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [161153]}, [161153, 346549]]], [['moderate losses between bounds', {'standard': 714988, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [147807, 50783, 101639, 147624]}, [447853, 714442]], ['large claim limited', {'standard': 1075364, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 600, 'max': 3000, 'loss_limit': 5000000, 'claims': [6621396, 51697]}, [5051697, 3226092]], ['maximum binds', {'standard': 636493, 'basic': 250, 'lcf': 1200, 'tax': 1050, 'min': 500, 'max': 1200, 'loss_limit': 5000000, 'claims': [3206066, 2811387, 2370852, 2596520]}, [10984825, 763792]], ['no losses minimum binds', {'standard': 1974481, 'basic': 200, 'lcf': 1200, 'tax': 1050, 'min': 500, 'max': 1600, 'loss_limit': 5000000, 'claims': []}, [0, 987241]], ['subrogation recovery offsets', {'standard': 1092045, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [210597, -95806]}, [114791, 366843]], ['net recovery floors at zero', {'standard': 1088467, 'basic': 250, 'lcf': 1200, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-13789]}, [0, 326540]], ['inverted bounds rejected', {'standard': 1508678, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 811592, 'basic': 250, 'lcf': 1200, 'tax': 1050, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 730433]], ['near-minimum losses', {'standard': 1513685, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [237641]}, [237641, 681158]]], [['moderate losses between bounds', {'standard': 1863348, 'basic': 250, 'lcf': 1200, 'tax': 1050, 'min': 400, 'max': 2000, 'loss_limit': 5000000, 'claims': [182396, 119506, 129126, 64521]}, [495549, 1113521]], ['large claim limited', {'standard': 1794820, 'basic': 200, 'lcf': 1100, 'tax': 1030, 'min': 500, 'max': 3000, 'loss_limit': 5000000, 'claims': [6997029, 30223]}, [5030223, 5384460]], ['maximum binds', {'standard': 1446879, 'basic': 200, 'lcf': 1200, 'tax': 1030, 'min': 500, 'max': 1200, 'loss_limit': 5000000, 'claims': [3226070, 2149089, 2381869, 2566788]}, [10323816, 1736255]], ['no losses minimum binds', {'standard': 1111989, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 500, 'max': 1400, 'loss_limit': 5000000, 'claims': []}, [0, 555995]], ['subrogation recovery offsets', {'standard': 930668, 'basic': 250, 'lcf': 1150, 'tax': 1030, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [215001, -125166]}, [89835, 346057]], ['net recovery floors at zero', {'standard': 790663, 'basic': 200, 'lcf': 1100, 'tax': 1050, 'min': 300, 'max': 2500, 'loss_limit': 5000000, 'claims': [-24524]}, [0, 237199]], ['inverted bounds rejected', {'standard': 901935, 'basic': 200, 'lcf': 1150, 'tax': 1050, 'min': 1300, 'max': 1200, 'loss_limit': 5000000, 'claims': [100000]}, 'invalid bounds'], ['flat plan with equal bounds', {'standard': 802066, 'basic': 250, 'lcf': 1150, 'tax': 1050, 'min': 900, 'max': 900, 'loss_limit': 5000000, 'claims': [100000]}, [100000, 721859]], ['near-minimum losses', {'standard': 1352189, 'basic': 250, 'lcf': 1150, 'tax': 1050, 'min': 450, 'max': 1800, 'loss_limit': 5000000, 'claims': [178467]}, [178467, 608485]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
moderate losses between bounds	`[455487, 780260]`	`[455487, 827175]`	Failed
large claim limited	`[5085219, 4610385]`	`[5085219, 4610385]`	Passed
maximum binds	`[14095709, 692363]`	`[14095709, 692363]`	Passed
no losses minimum binds	`[0, 391659]`	`[0, 391659]`	Passed
subrogation recovery offsets	`[227452, 533320]`	`[227452, 581085]`	Failed
net recovery floors at zero	`[0, 591265]`	`[0, 591265]`	Passed
inverted bounds rejected	`invalid bounds`	`invalid bounds`	Passed
flat plan with equal bounds	`[100000, 929482]`	`[100000, 929482]`	Passed
near-minimum losses	`[196003, 469147]`	`[196003, 509523]`	Failed

SHA-256 / b4053ea2c4064983ca42dc189b390f821d379e8830e80812f2ba2b7c633eac57

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 9 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

Verification & scope

A deterministic bounded teaching model of a stipulated toy rating contract. Amounts are integer cents and factors exact rationals; it makes no claim of conformance with any filed rating plan, bureau manual or jurisdiction. 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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:47:12.324739+00:00.

Case digest / ba962da538800bf6f84ffcdd5215dfc6f2e1f54a7eef3b8dba6f0539394a0aae