FA-65104 / Epidemic compartment models / Member archive

Age-structured force of infection: susceptibility multiplier · case 04

Groups with reduced susceptibility are infected at full rate.

Member previewVariant 4 · 3 implementations · 7 checks per implementation

Case contract

lambda[a] = beta*susceptibility[a]*sum_b contacts[a][b]*infected[b]/sizes[b] (groups with zero size skipped); expected new infections susceptible[a]*(1-exp(-lambda[a])); return [lambdas rounded 6, new infections rounded 4, total rounded 4].

Why this case matters

Compartmental epidemic calculations drive outbreak forecasts, vaccine targets and hospital planning; a single wrong flow, rate conversion or boundary silently changes every downstream number.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
regression: empty elderly band	`[[0.038, 0.046, 0.014], [3.3558, 4.271, 0.0], 7.6268]`	`[[0.038, 0.046, 0.021], [3.3558, 4.271, 0.0], 7.6268]`	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.