Econometricians Can Build Decision Engines
A source-backed explanation of how causal models turn business inputs into decision rules, and why the bottleneck is often authority rather than math.
Causal Decision Systems
Why Mean-Variance Optimization Is an Error Maximization Machine
Mean-variance optimization systematically overweights the assets you're most wrong about. An interactive demo of Michaud's critique, with practical alternatives for fiduciary advisors.
Portfolio Construction
Hierarchical Bayesian Neural Networks: When Structure Meets Flexibility
Adding hierarchical BNNs to the comparison — combining group structure with neural network flexibility for the lowest prediction error when data has both.
Bayesian Methods
Bayesian Hierarchical Model vs Bayesian Neural Network vs Ensemble: When Structure Beats Flexibility
A reprex comparing Bayesian hierarchical models, Bayesian neural networks, and their ensemble on out-of-sample CRPS across two data-generating processes.
Bayesian Methods
Why Is Gold Falling? High Real Rates & Oil Shock Inflation
Gold doubled in two years, but high real yields, oil-shock inflation, and liquidation risk may be turning the rally into a crowded unwind.
Macro & Commodities
Poisson-Gamma Negative Binomial
The equivalence between the Negative Binomial distribution and the Poisson-Gamma mixture, with R simulations.
Counting Processes
Geometric Distribution & Bayesian Updating
Conjugate priors and sequential Bayesian updating demonstrated with the Geometric distribution.
Bayesian Methods
Simulating Right-Censored Weibull Data
Building a right-censored Weibull random number generator for survival analysis validation.
Survival Analysis
Bayesian Right-Censored Weibull Model
Comparing Frequentist and Bayesian estimation of Weibull parameters with brms.
Bayesian Survival
R's library() Function Dissected
A line-by-line walkthrough of R's most commonly called function.
R Internals
Are Boeing Planes More Dangerous Than Airbus?
NTSB event analysis normalized by departures shows Boeing at 1.7x more events per 100k flights.
Aviation Safety
purrr's pmap: Mapping Functions to Data
From map to map2 to pmap, generalizing functional iteration over arbitrary inputs in R.
R Programming
Bernoulli Experiments & Stan MCMC
Building a likelihood function from scratch and estimating parameters with Stan's MCMC sampler.
Bayesian Methods
Weibull Characteristic Life
Deriving and interpreting characteristic life with simulations and reliability framing.
Survival Analysis
Technology Diffusion
How innovation spreads through society via contagion, reinforcement, network effects, and institutions.
Innovation Theory
Spillovers and Peer Effects
A literature-backed guide to spillovers, peer effects, social multipliers, and how economists identify them.
Economics Literature