## Problem 135 — rank:273

**Title:** Cell competition

**Added binding assumptions (LaTeX):**

```latex
Interpret the death rate as a predictable intensity conditional on the observed history, not as a hazard conditioned on a future endogenous neighbor trajectory. Include division, migration and other competing events in that history. Require nonnegative total rates even if the interaction contribution can have either sign. Solitary-cell and matched-neighbor controls anchor the decomposition into baseline fitness and competition effects.
```

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