## Problem 215 — rank:99

**Title:** Spread of antimicrobial resistance

**Added binding assumptions (LaTeX):**

```latex
Use the displayed proportion only for $n_t>0$, and define the joint sampling law conditional on testing volume and observed covariates. Measurement sensitivity and specificity need external information or explicit bounds; changes in either can imitate resistance-frequency trends. A latent multicomponent state-space model is not identified by naming its components. Report only functionals that are constant across its observable equivalence class.
```

**Direct edits:** 0. **Fresh external checks:** None; supplied sources retained as provenance.