Writing & football analytics
CannonIQ
An Arsenal newsletter combining statistical modelling, economics and long-form writing, read by more than 500 subscribers.
Explore CannonIQ ↗London · Risk modelling & data engineering
Stephen
Ahiabah.
Nine years building risk models and the data behind them.
NatWest, then JPMorgan Chase. Outside work, I build small research apps and write about Arsenal on CannonIQ.
Credit risk → model development → data engineeringScroll to explore ↓
01 / Experience over time2017—2026
Normal curve / career timeline05 / 05
JPMorgan ChaseSep 2026—present
Data Engineer
Tracing critical data across Asset & Wealth Management, with lineage, quality checks and preventative controls.
BCBS 239 · lineage · data quality02 / Outside the day job
The other projects.
Football, finance, music and the data underneath. Pick a project to follow the connections.
Six projectsShared methods
What I work on
Three areas I keep coming back to
Most of my work sits where a model, a dataset and a business decision have to agree.
Credit risk modelling
Loss forecasting, IFRS 9 and CECL provisioning, PD models and stress testing, from development through governance and senior review.
- NatWest UK Retail
- JPMorgan Chase ICB Risk
Data engineering
Pipelines, lineage and data quality controls that make critical data traceable and ready for analytics and AI.
- PySpark, SQL, Python
- BCBS 239 lineage
Statistics in public
Independent projects and writing where I test new methods, from Bayesian updating to Monte Carlo, and explain them in plain English.
- CannonIQ
- Pitch IQ
Track record
Selected results from nine years in banking
Numbers from my work at NatWest and JPMorgan Chase. The details are on the experience page.
| £200bn | UK retail portfolio covered by the stress testing and loss forecasting I co-led | NatWest |
| 60 → 10 min | IFRS 9 staging runtime after I directed its rebuild from SAS to Python | NatWest |
| 2 FTE | Recurring manual work removed by a roll-rate model and automated forecasting | JPMorgan Chase |
| 7+ | Inherited model risk issues cleared in my first year as lead model developer | JPMorgan Chase |
| 100+ | Colleagues moved onto SageMaker, CI/CD and GitHub across ICB Risk | JPMorgan Chase |
Recent projects
Finance research and data engineering
Two Streamlit apps built around public datasets, with the methods and code available to inspect.
Writing · CannonIQ
Statistics in public, for 500+ readers
CannonIQ is my Arsenal publication on Substack. It's where I test new methods and explain them in plain English.
Model notes · 2026
Goals Are Rare
Poisson, weighted rolling averages, Bayesian updating and Monte Carlo, explained for football people.
↗ Expected points · 2026The Table Lies to You (A Bit)
Why a probabilistic view of team strength tells us something the league table can't.
↗ Recruitment · 2025Finding Arsenal's "Win Now" Forward
A Random Forest model for projecting goal contributions and testing shortlists.
↗ Long-form · 2026Same Old Arsenal. Same Old Lie.
A personal essay on fandom, narratives and what statistics can't settle.
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