Tail Risk, Extreme Value Theory, and Clearinghouse Margin Mechanics: Fat Tails, Peaks-Over-Threshold, Copula Failures in 2008, VaR vs Expected Shortfall, and CCP Default Waterfalls

Deep End Era. Engineering with Sankalp · Oct 29, 2026 · 1h 46m

How should a risk engine handle extreme losses and joint crashes? This episode examines fat tails, extreme value theory, copulas, VaR and expected shortfall, then follows initial margin, procyclicality, default waterfalls and historical clearinghouse failures.

Chapters

00:00:00 Chapter 1: Cold Open — Why Black Monday 1987 Was a 22-Sigma Event Under a Gaussian Bell Curve, How a Single Formula Blew Up the 2008 CDO Market, and How One Trader Breached a Clearinghouse Waterfall!

00:06:11 Chapter 2: Why Financial Returns Obey an Inverse-Cubic Power Law $P(|rt| > x) \sim x^{-3}$ — Mandelbrot (1963)…