predict + reliability, in other words: A tool to predict the reliability.
predictr is a Python package for Weibull-based life data analysis (reliability engineering). It covers parameter estimation, bias-correction, confidence bounds, and publication-ready Weibull plots in a single, consistent API.
pip install predictrRequires Python >= 3.6.
from predictr import Analysis
failures = [0.4508831, 0.68564703, 0.76826143, 0.88231395, 1.48287253, 1.62876357]
weibull = Analysis(df=failures, bounds='fb', show=True)
weibull.mle()
print(weibull.beta, weibull.eta) # shape and scale estimatesThis fits a two-parameter Weibull distribution via Maximum Likelihood Estimation, adds Fisher confidence bounds, and renders the probability plot below.
A few of predictr's capabilities, from bias-corrected estimates to comparing entire distributions.
| Bias-corrected estimates | Confidence region, multiple levels |
|---|---|
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| Ranked by AIC | Distributions compared |
|---|---|
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Parameter estimation
- Uncensored and type I / type II right-censored two-parameter Weibull distribution
- Maximum Likelihood Estimation (MLE) and Median Rank Regression (MRR)
- Bx-life calculator
- Normal, LogNormal and Exponential distributions, alongside Weibull
Bias-correction
- C4 method (reduced bias adjustment)
- Hirose and Ross method
- Parametric and non-parametric bootstrap correction (mean, median, trimmed mean)
Confidence bounds
- Fisher bounds
- Likelihood Ratio bounds (Weibull, Normal, LogNormal)
- Beta-Binomial bounds
- Monte Carlo Pivotal bounds
- Parametric and non-parametric bootstrap bounds
- Exact chi-square bounds (Exponential)
Plots
- Probability plots with all relevant statistics in the legend
- Multiple fits overlaid in one figure, for design comparisons
- Contour plots for the joint confidence region of shape and scale, with support for multiple confidence levels per dataset
- Distribution comparison: fit every supported distribution to one dataset, ranked by AIC or Anderson-Darling, plus a combined PDF plot
See the class documentation for the full method and parameter reference, including censored-data and bias-correction examples.
If you use predictr in academic work, please cite it via its Zenodo DOI. See docs/citation.md for details.
MIT — see LICENSE.txt.
If you have any questions and / or suggestions, don't hesitate to contact me.




