Reference desk
Weibull Parameter Reference
Quick definitions for the two-parameter Weibull model and the reliability quantities derived from it.
| Term | Meaning | Formula |
|---|---|---|
| η | Characteristic life; reliability is 36.8% at η. | Time unit |
| β | Shape; below 1 decreasing, above 1 increasing hazard. | Dimensionless |
| R(t) | Survival probability at time t. | exp[−(t/η)^β] |
| h(t) | Conditional failure intensity. | (β/η)(t/η)^(β−1) |
Fitting caution
Parameters depend on data quality, censoring treatment, population consistency, and failure-mode separation. Always attach a model scope and confidence statement to a published estimate.
Related tools
Weibull reliability, B10 life, hazard rate, and Weibull analysis guide.