uncertainty-and-unitslisted
Install: claude install-skill timsmykov/evidence-lab-plugins
# Uncertainty and units
## Scope
Use this skill whenever a calculation carries physical units or a reported number needs
an uncertainty. Concretely:
- converting between units, including conversions that need a physical context
(wavelength to photon energy, mass to amount of substance, energy to temperature);
- propagating uncertainty through a measurement model, with or without correlated inputs;
- building a GUM uncertainty budget from calibration certificates, specifications, and
repeatability data;
- choosing a coverage factor and deciding whether `k = 2` is defensible;
- rounding and writing a result so a reader knows what the `±` means;
- extracting parameter uncertainties from a curve fit without discarding correlations;
- reviewing existing analysis code for silent unit and uncertainty defects;
- checking that a dimensionally consistent answer is also physically possible — the
order of magnitude, the dimensionless group, and the regime it implies.
This skill covers the metrology and the two libraries that implement it. It does not
cover statistical inference, model selection, or study design — see `statistical-analysis`,
`statistical-power`, and `experimental-design`.
## Current release and installation
Verified 2026-07-26:
- **pint 0.25.3**, released 2026-03-19; requires Python 3.11+.
- **uncertainties 3.2.3**, released 2025-04-21; requires Python 3.8+.
- **NumPy 2.5.1** and **SciPy 1.18.0**; both require Python 3.12+.
- `scipy.constants` in SciPy 1.18.0