AI · DATA SCIENCE · QUANTITATIVE FINANCE

I build intelligent systems for problems where uncertainty matters.

I’m Rancy Chepchirchir — an AI researcher, data scientist and quantitative finance practitioner working across trustworthy AI, financial machine learning, scientific machine learning, computer vision and NLP.

Portrait of Rancy Chepchirchir
Open to research & technical collaborations
Currently thinking about

Trustworthy AI, foundation models, uncertainty, financial event sequences & model governance.

THE THREAD

Different domains. Same question: how do we build intelligent systems that remain useful, interpretable and reliable when uncertainty is part of the problem?

SELECTED RESEARCH

Questions worth staying with.

Research spanning quantitative finance, trustworthy machine learning and AI systems that must operate under uncertainty.

01
Computer VisionTrustworthy AIDeep Learning

Exploring Deepfake Detection: A Comparative Analysis

A comparative investigation of deepfake detection architectures, examining how different deep-learning approaches perform on manipulated-media classification and what their trade-offs imply for robust, trustworthy detection systems.

02
Medical AIComputer VisionDomain Adaptation

Generative Style Transfer for MRI Image Segmentation

Brain-tumour segmentation for Sub-Saharan African MRI data, combining nnU-Net, cross-domain evaluation and generative style-transfer augmentation to improve robustness under lower-resource imaging conditions.

03
Quant FinanceHigh-Frequency Data

High-Frequency Covariance Estimation & Portfolio Optimisation

Studying covariance estimation under market microstructure noise and evaluating estimators from the portfolio-selection perspective, including QMLE and high-frequency return constructions.

04
Scientific MLDerivatives

Neural Operators & Physics-Informed Methods for Option Pricing

Comparing PINNs, DeepONets and classical finite-difference methods for derivative pricing, with particular interest in American options, PDE constraints and uncertainty-aware approximation.

05
EconometricsCommodity Markets

Commodity Futures & Spot-Market Volatility

Empirical analysis of futures introduction and spot volatility across agricultural commodities and markets using ARCH, GARCH and EGARCH modelling.

FEATURED WORK

Research that becomes systems.

A curated selection of systems, experiments and research prototypes rather than an exhaustive repository list.

RESEARCH EVIDENCE

Selected cards expose methods, measured results and model behaviour directly — not just project descriptions.

nnU-NetMRIDomain Adaptation

Brain Tumour Segmentation

Glioma segmentation under domain shift, combining nnU-Net experiments with generative style-transfer augmentation for Sub-Saharan African MRI data.

DICE COEFFICIENThigher is better · selected experimental results
Whole tumour0.659
Tumour core0.629
Enhancing0.819
Read paper
PINNsDeepONetsPDEs

Option Pricing Laboratory

A small interactive bridge between classical quantitative finance and scientific machine learning. Change the market assumptions and watch the Black–Scholes European call benchmark respond.

MODEL PRICE European call · Black–Scholes benchmark
BLACK–SCHOLES PDE Vₜ + ½σ²S²Vₛₛ + rSVₛ − rV = 0

The live calculator uses the closed-form European call benchmark; my broader work compares classical numerical solvers with PINNs and neural operators for PDE-based pricing.

NLPSign LanguageLow-resource AI

African Language & Sign-Language AI

Applied NLP and visual-language work including Kenyan Sign Language and Swahili.

View project
TransformersEvent DataUncertainty

Sequential Foundation Models

Representation learning for financial event streams and uncertainty-aware decisions.

Discuss research
Next.jsPostgreSQLKnowledge Systems

Codex — Personal Knowledge OS

A personal library and knowledge system for books, notes, ideas, search and AI-assisted retrieval.

GitHub

ABOUT

Numbers taught me precision.
AI taught me uncertainty.

My path into AI began in financial economics and mathematical finance, where uncertainty is not a nuisance to remove but a quantity to model.

That perspective still shapes how I approach machine learning: I care about what a model predicts, but also why it predicts it, how reliable that prediction is, how it behaves when the world changes, and what happens when people rely on it.

My work has moved through quantitative finance, data science, NLP, computer vision, medical imaging and AI safety. Across those areas, the underlying question remains surprisingly consistent: how do we build intelligent systems worthy of the decisions we ask them to make?

OFF THE CLOCK

Reader of philosophy and literature. Student of Stoicism by inclination. Builder of personal knowledge systems by habit.

HOW MY RESEARCH CONNECTS

Different domains. Recurring questions.

Hover or focus on a node to see the projects and ideas it connects to. The common thread is reliability under uncertainty.

EXPERIENCE & EDUCATION

A deliberately interdisciplinary path.

Jan 2024 — Present

Course Instructor

LinkedIn Learning

Technical education and applied data-science content, including Python for finance.

Apr 2023 — Feb 2025

Data Scientist · NLP

Derivation LLC

NLP systems, data applications, model development and applied machine-learning workflows.

May 2024 — Jul 2025

MSc Artificial Intelligence & Data Science · Distinction

University of Hull

Deepfake detection, deep learning, computer vision and trustworthy machine learning.

2021 — 2022

Financial & Research Analyst

Maitri Capital

Financial research, quantitative analysis and data-driven investment work.

Apr 2018 — Jun 2020

MSc Financial Engineering

WorldQuant University

Derivatives, econometrics, risk, portfolio theory and computational finance.

Jan 2011 — Jun 2015

BBS Financial Economics

Strathmore University

Economics, finance, statistics and quantitative methods.

RESEARCH INTERESTS

The recurring threads.

Trustworthy AI AI Safety & Evaluation Foundation Models Financial Machine Learning Scientific Machine Learning Computer Vision Natural Language Processing Privacy-Preserving ML Uncertainty Quantification Model Governance

SELECTED RECOGNITION

Milestones that shaped the work.

A small selection of conferences, programmes and awards that mark important stages in my research journey.

2024

MICCAI 2024

Paper accepted with a poster presentation in medical imaging research.

2023

MICCAI Vancouver

Received LACUNA Fund support to attend MICCAI and presented a poster.

2023

Big Data Africa School

Won both Most Progress and Best Team.

2023

SPARK Academy

Accepted into the medical-imaging training programme.

2015

PARTY5 Risk Management

Paper accepted for presentation in Liverpool.

ONGOING

Mentoring

Mentor with Coding Black Females, supporting students and early-career technologists.

CURRENTLY

A small window into what has my attention.

The portfolio is the archive. This is the moving part.

RESEARCHING

Trustworthy multimodal AI

Robustness, provenance, uncertainty and governance for systems that operate across modalities.

BUILDING

Codex

A personal knowledge OS for books, notes, ideas, search and AI-assisted retrieval.

THINKING ABOUT

When should we trust uncertainty?

Not merely whether a model is confident, but whether its confidence means what we think it means.

WRITING

Technical notes & stories

Machine learning, finance, research field notes, philosophy and whatever refuses to leave my head.

WRITING

I write to understand things.

Technical notes, project stories and occasional field notes — on machine learning, quantitative finance, research, people and the questions that stay with me.

BEYOND THE MODELS

There is life outside loss functions.

When I’m not training models or solving PDEs, you’ll find me reading, writing, playing the guitar, watching football, travelling, and chasing ideas that do not always fit neatly into a dataset.

Stylized portrait of Rancy playing guitar, blending music, creativity and technology
Research is part of the story. Curiosity is the larger one.
01 / MUSIC

Strings, slowly learning.

Music keeps a different kind of time — less measurable, still worth learning.

02 / BOOKS

Ideas with long half-lives.

Philosophy, literature, history and books that leave behind better questions.

03 / STORIES

Writing to understand.

Sometimes technical, sometimes personal, always an attempt to understand or remember.

LET’S TALK

Good problems are rarely solved alone.

I’m interested in conversations around trustworthy AI, AI safety, financial ML, scientific machine learning, research collaborations and ambitious technical projects.

Coffee is also an acceptable protocol.