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Experimental design, data analysis, and statistical tooling for modern teams. No hype, just the math.

Accelerated Failure Time Models: When Cox Doesn't Fit
Survival AnalysisJan 29New

Accelerated Failure Time Models: When Cox Doesn't Fit

When proportional hazards fail, AFT models offer an interpretable alternative. Learn when to use accelerated failure time models, how to interpret time ratios, and how they compare to Cox regression.

Autocorrelation: Why Your Daily Metrics Aren't Independent
Time SeriesJan 29New

Autocorrelation: Why Your Daily Metrics Aren't Independent

Learn why autocorrelation in product metrics invalidates standard tests, how to detect it, and what corrections to apply.

Bayesian A/B Testing: Posterior Probabilities for Ship Decisions
Bayesian MethodsJan 29New

Bayesian A/B Testing: Posterior Probabilities for Ship Decisions

How to run Bayesian A/B tests that give you the probability a variant wins. Practical guide with Python code for conversion rates and revenue metrics.

Bayesian Hierarchical Models: Borrowing Strength Across Segments
Bayesian MethodsJan 29New

Bayesian Hierarchical Models: Borrowing Strength Across Segments

How hierarchical Bayesian models share information across segments to improve estimates. Learn partial pooling, when it helps, and how to implement it.

Bayesian Regression: When Shrinkage Improves Predictions
Bayesian MethodsJan 29New

Bayesian Regression: When Shrinkage Improves Predictions

Learn how Bayesian regression uses priors as regularization to improve predictions. Practical guide to shrinkage, uncertainty quantification, and when it beats OLS.

Bayesian Sample Size: Why It's Different and When It Helps
Bayesian MethodsJan 29New

Bayesian Sample Size: Why It's Different and When It Helps

How to plan sample sizes for Bayesian experiments. Learn why Bayesian sample sizing differs from frequentist, and when it gives you smaller or more flexible experiments.

Bayesian vs. Frequentist: A Practical Comparison for Analysts
Bayesian MethodsJan 29New

Bayesian vs. Frequentist: A Practical Comparison for Analysts

Side-by-side comparison of Bayesian and frequentist methods for product analysts. Learn which approach fits your problem, team, and decision context.

Change Point Detection: When Did the Metric Shift?
Time SeriesJan 29New

Change Point Detection: When Did the Metric Shift?

How to detect when a product metric changed using PELT, CUSUM, and Bayesian change point detection methods.

Cochran's Q Test: McNemar for Three or More Conditions
Multi-Group ComparisonsJan 29New

Cochran's Q Test: McNemar for Three or More Conditions

A practical guide to Cochran's Q test for comparing binary outcomes across three or more related conditions. Learn when to use it, how to interpret results, and post-hoc follow-ups.

Confounding: The One Thing That Breaks Every Observational Study
Causal InferenceJan 29New

Confounding: The One Thing That Breaks Every Observational Study

What confounding is, why it invalidates naive causal claims, and how to identify and handle confounders in product analytics and observational studies.

Credible Intervals vs. Confidence Intervals: What Changes
Bayesian MethodsJan 29New

Credible Intervals vs. Confidence Intervals: What Changes

Understand the real difference between credible and confidence intervals. Learn what each actually means, when it matters, and how to interpret both correctly.

DAGs for Analysts: Drawing Your Assumptions Before You Analyze
Causal InferenceJan 29New

DAGs for Analysts: Drawing Your Assumptions Before You Analyze

How directed acyclic graphs help analysts identify confounders, avoid collider bias, and choose the right variables to control for in causal analysis.