Back Story

TL;DR: I wanted to better understand the mechanics of a modern monetary system. View the reading.

I'm a full-time carer for my disabled mum. It seems an age since I was technical and training lead for a number of transnational accounting system projects; Enterprise Resource Planning (ERP) to use the lingo. During this time I opened a self-invested private pension (SIPP). I made regular contributions for a while. But that was then, my SIPP lay dormant, forgotten for years. Then one day I received an email. "Your SIPP has a high proportion held as cash" read the headline. It was my SIPP provider. They continued, "... This might be part of your strategy, but it can drag on returns." Strategy? I didn't know whether to laugh or cry. What strategy? I ignored it, a high proportion of not much is not much. But it gnawed at me. I should do something. Near-term, my choice was simple, so I thought, invest in a government bond fund. Thing is, it didn't feel simple. Nothing post 2008 financial system collapse felt simple. What was this system? I remember undergraduate economics, just, the certainty of lectures articulating the efficient markets hypothesis and the risk free asset. I knew nothing beyond a generally received narrative. I wanted to know more.

Accomplished Teachers

In the summer of 2018 I bought Crashed; a then recently published analysis of the 2008 financial crisis written by Adam Tooze. Thanks to the recommendation algorithm I bought two further books soon after, these being, Monetary Economics written by and Marc Lavoie (G&L) and Making Money written by Christine Desan. Desan explores the evolution of the English monetary system through the ages - a simply fascinating account - with the power to historicise G&L's meticulous models. While metallism narrates the compound money of earlier times, it was a system - a monetary system - that bestowed on precious metals a cash price. Today, a government with the authority and power to create currency will issue bonds in order to drain reserve balances and produce collateral.

By late 2022 it dawned on me that the wonderful books and academic papers I have mostly read since 2018 were each a lens through which to view a particular social system - one of power, resources and the distribution thereof. Laterly, the exceptional work being done by the economists at the University of the West of England, Bristol has come into view. From this reading we learn institutions have evolved modern money into market-based finance. A pro-cyclical, collateralised, bond price sensitive system to completely absorb the theme of Tooze's tome.

Model Endeavours

My reading continued. Some of the academic texts allowed me to construct my own simple accounting treatments (old habits). Eventually, however, it was time to focus on G&L's book. Specifically, I wanted to understand the early chapters, G&L's incrementally sophisticated sectoral accounting explanations of a government money system. I set out to build my own computational (agent-based) model interpretations of the G&L described systems. At the very least, I'll keep my tools sharp and have fun doing so.


Models are written in the Python computer programming language. Project Mesa is the agent-based modelling framework used. Model abmlp, the third model described, is a work in progress.

On Models

No model is the world. The well known aphorism "all models are wrong, but some are useful" comes to mind. I make every effort to ensure the accounting at the core of my agent-based models faithfully reproduce G&L descriptions. Models spring from my nascent, bounded, comprehension of reading materials describing a simple monetary system.

View an architectural sketch .

Author: Dan O'Driscoll. Email: Visit studio-data-reports .

Previous employment: Japanese sogo-shosha, a professional service and major energy transmission company. Further education: Undergraduate degree in Business & Economics (BA): Postgraduate degree in Computer Security Forensics & Risk Management (MSc). Based near London, England.