FA-99116 / Learning rate schedules / Open access
Linear decay ignores the configured minimum rate · case 01
Linear decay ignores the configured minimum rate.
ROOT CAUSE
The decay formula is hard-coded to approach zero instead of the configured floor.
THE FAILURE
The decay formula is hard-coded to approach zero instead of the configured floor.
Unsuccessful approach: Applying the floor only before the endpoint still returns zero at the endpoint.
Case contract
Linearly decay from base to floor across total steps and clamp at both endpoints.
Why this case matters
A deterministic scalar schedule makes step-to-rate mapping explicit for a small training loop.
1 / The failure
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(step, base, floor, total):
return base*max(0,1-step/total)
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('start',solve(0,10,2,4),10); check('quarter',solve(1,10,2,4),7.5); check('mid',solve(2,10,2,4),5); check('floor',solve(4,10,2,4),2); check('after',solve(6,10,2,4),2); check('equal floor',solve(0,3,3,4),3)
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 |
|---|---|---|---|
| start | 10.0 | 10 | Passed |
| quarter | 7.5 | 7.5 | Passed |
| mid | 5.0 | 5 | Passed |
| floor | 0 | 2 | Failed |
| after | 0 | 2 | Failed |
| equal floor | 3.0 | 3 | Passed |
SHA-256 / 7d6ead06558665dc1087be7b98c2774e9cd266099759d41ee431ec2815fdf35a
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(step, base, floor, total):
return max(floor,base*(1-step/total)) if step<total else 0
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('start',solve(0,10,2,4),10); check('quarter',solve(1,10,2,4),7.5); check('mid',solve(2,10,2,4),5); check('floor',solve(4,10,2,4),2); check('after',solve(6,10,2,4),2); check('equal floor',solve(0,3,3,4),3)
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 |
|---|---|---|---|
| start | 10.0 | 10 | Passed |
| quarter | 7.5 | 7.5 | Passed |
| mid | 5.0 | 5 | Passed |
| floor | 0 | 2 | Failed |
| after | 0 | 2 | Failed |
| equal floor | 3 | 3 | Passed |
SHA-256 / 5d3a82374d5c7b1fea7e07a912ca57fcf8fcf412ae7aa81df2281d312afc2acd
HELD IN THE MEMBER ARCHIVE
The verified repair and its recorded checks are member-only.
This mechanism has 6 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.
Sign in to the archive ↗Verification & scope
These are toy scalar contracts with integer steps and finite parameters; they do not model framework defaults or optimizer state. 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 2026-09-30T16:48:20.350830+00:00.
Case digest / 67c45ee72902799bfc72dd565944965a33ee338350f260a5ff6615ad17d40daa