chariblog - technical writings in applied science – chariblog

The Beautiful Frisch–Waugh–Lovell Theorem

frisch-waugh-lovell

yule-frisch-waugh-lovell

ordinary-least-square

There are few results in econometrics that feel as magical as the (Yule-)Frisch–Waugh–Lovell (FWL) Theorem. In this article, we will trace how it is derived analytically and…

Understanding Double/debiased Machine Learning (DML)

causal-inference

double-machine-learning

frisch-waugh-lovell

neyman-orthogonality

Double/debiased machine learning (DML) is one of the most prominent causal inference algorithms in modern practice from pricing, promotion targeting to multi-million-dollar…

AI Builders Survey 2025: What Five Years of Teaching Kids to Build Good AI Looks Like

ai-builders

education

survey

AI Builders is a 10-week, online program that teaches middle-to-high school students in Thailand to create an ML project they can be proud of. Every year, we select 40-60…

(Almost) All SQL You Need

sql

tutorial

Skill mastery is an endeavor of diminishing returns. You can get from zero to good enough (think first-time chess player to 500 online rating) within 100 hours of deliberate…

Predict How Much A Customer Will Spend

retail

zero-inflated

long/fat-tailed

hurdle

I have spent nearly a decade as a data scientist in the retail sector, but I have been approaching customer spend predictions the wrong way until I attended Gregory M. Duncan…

How to Have a Robustly Interesting Career in Data Science

career

I have been a data scientist👨‍💻 ever since around the time HBR popularized the term in its job sexiness article. My run started out of necessity, since back then it was…