Research by T. Zamrik

Welcome. This is where I keep my research: working papers on stochastic analysis, control and mean field games, and a Notebook that takes a question from the world and works it through to the mathematics, with data and models you can run in the browser. The newest of each is just below. — T. Zamrik

36 papers since 2022 · 53 notebook posts · 6 research areas

Latest

From the Notebook

The Forest That Burns All at Once

Forty BC fire seasons: fire counts varied 6-fold, area burned 957-fold. A percolation threshold and a fire PDE on patchy fuel explain why. Live map.

The Barrier That Comes Early

A price at $100 takes nine years on average to reach $120, yet has a 40% chance within a year. The GBM hitting-time formula and up-and-out options.

The Wave That Nobody Ordered

Customer demand steps once from 4 to 8 cases a week, yet factory orders swing to 33. The Beer Game as 27 differential equations, with a live simulator.

New papers

The Price of a Yaw: Optimal Deadbands and Filters for Wind-Turbine Yaw Control, Calibrated on SCADA Data

A wind turbine must keep its rotor facing a wind whose direction never stops moving, and every yaw that realigns it wears the yaw system.

Dividends When Capital Is Slow: de Finetti’s Problem with a Sticky Boundary

Dividend models give a firm at zero surplus two fates: it is ruined, or capital arrives instantly and reflects it back into business.

The Derived Time Stop

A swing trade is a hypothesis with a deadline.

All 53 essays →All 36 papers →


Research interests

I work on stochastic analysis and optimal control, and on what happens when many decision-makers optimise at once: mean field games, market models and mathematical finance. A typical paper starts from a practical question, when to act and how hard, and ends with an equation solved as explicitly as it allows and checked numerically.

Browse by area

Every area, and what each one covers →

Watercolor of stochastic analysis

Reading and citing

Most papers, and the whole Notebook, are free to read; a few papers are restricted. Every paper carries its own serial number, printed on the paper and in its address, so a citation always points at one document (how to cite). Where a paper’s code is published, it is on GitHub, at github.com/Dr-Zamrik, so its numbers can be re-run rather than taken on trust.

The Notebook starts from a story and ends in the mathematics, with data, code and live models; some essays grow into papers.

Watercolor interplay of stochastic analysis and stochastic control