FA-71704 / Seismic magnitude estimation / Member archive

Richter -log A0 table magnitude: log-domain component average · case 04

Unequal component amplitudes bias ML upward.

Member previewVariant 4 · 3 implementations · 8 checks per implementation

Case contract

Zero-to-peak Wood-Anderson amplitudes on two horizontal components in mm (0 = dead channel, ignored; both dead returns None). -log A0 is linearly interpolated from [(0,1.4),(10,1.5),(20,1.7),(30,2.1),(50,2.6),(100,3.0),(200,3.5),(300,4.0),(400,4.5),(600,5.1)] with 0 <= dist <= 600 inclusive, else None. ML = mean of per-component log10 amplitudes + (-log A0), rounded 0.01.

Why this case matters

Classic ML reproduces Richter tables for historical catalogue homogenisation.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
N 0.05 mm E 0.08 mm at 5 km	`0.26`	`0.25`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

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