Christophe is available for hire
Hire ChristopheChristophe Williams
Verified Expert in Engineering
Data Science Developer
Arlington, VA, United States
Toptal member since March 12, 2020
Bio
Christophe holds an MBA from Wharton and leads Cedar Labs, a data science consultancy. He has ten years of data science experience across Capital One, Amazon, the 2012 Obama campaign, and several startups. Christophe has expertise in finance, marketing, and retail. His specialties include data strategy and architecture, hiring data teams, time series and forecasting, regression and classification, machine learning, NLP, analytics, and ETL/pipelines.
Portfolio
Cedar Labs
Amazon Web Services (AWS), Serverless, Node.js, Python...
Foundry.ai
Amazon Web Services (AWS), Elasticsearch, Node.js, Serverless, Docker...
CitySense Technologies
Amazon Web Services (AWS), Elm, JavaScript, RStudio Shiny, R, Leadership...
Experience
- Python - 9 years
- Time Series Analysis - 9 years
- SQL - 8 years
- Machine Learning - 6 years
- Data Visualization - 5 years
- Data Pipelines - 5 years
- Tableau - 4 years
- Amazon Web Services (AWS) - 4 years
Work Experience
CEO
2019 - PRESENT
Cedar Labs
- Led data science consulting practice, focusing on data strategy and growth-oriented data services.
- Served as fractional chief data officer for early-stage startups: set strategy, built capabilities and products, hired talent.
- Supported user acquisition, forecasting, resource allocation, product development; specialized in fintech and SaaS companies.
- Offered the following services; strategy, governance, hiring data teams, architecture, predictive analytics, time series analysis, regression, classification, recommendation systems, machine learning, natural language processing, ETL, and pipelines.
Technologies: Amazon Web Services (AWS), Serverless, Node.js, Python, Artificial Intelligence (AI), OpenAI, Data Science, Data Analytics, Data Analysis, Predictive Modeling, Data Visualization, Big Data, Pricing Models, ROI, Executive Consulting, Web Scraping, Java, Large Language Models (LLMs), Forecasting, Predictive Analytics, Data Engineering, System Modeling, Marketing Mix Modeling, Data Scientist, Bayesian Statistics, Media Mix Modeling, Time Series Analysis, Statistics, Marketing Science, ARIMAX, Google Analytics 4 (GA4), Time Series Data, Time Series Forecasting, Marketing Mix, Multi-touch Attribution, Time Series, CRM, Google Ads, Econometrics
Lead Data Scientist
2018 - 2019
Foundry.ai
- Served as general manager of hud.ai (the second oldest portfolio company within the Foundry.ai startup studio): led the product roadmap, data science, business development, and customer success.
- Built dozens of new feature sets/models across full stack, coordinating in-house and offshore developer teams and doubling sales. Executed pivot in product strategy, built new product and go-to-market strategy.
- Built NLP models with TensorFlow and Scikit-learn, deployed using Docker, Serverless/Lambda, and scaled with Node and elasticsearch.
- Developed new ETL process and built data pipelines from scratch for large text datasets, using Python, Selenium, AWS Lambda + Layers, and both Postgres and a data lake.
- Consulted for telecom company and built advanced predictive models for buying propensity, customer churn, and marketing campaign effectiveness. Built large competitive intelligence system using cloud-based crawlers, which along with first-party data were used to train and update predictive models.
Technologies: Amazon Web Services (AWS), Elasticsearch, Node.js, Serverless, Docker, TensorFlow, Scikit-learn, Python, Artificial Intelligence (AI), Leadership, Data Science, Data Analytics, Data Analysis, Predictive Modeling, Data Visualization, Big Data, Executive Consulting, Web Scraping, Java, Forecasting, Predictive Analytics, Data Engineering, System Modeling, Data Scientist, Bayesian Statistics, Time Series Analysis, Statistics, Bayesian Inference & Modeling, Marketing Science, ARIMAX, Time Series Data, Time Series Forecasting, Time Series, CRM
Co-founder, Head of Product
2016 - 2018
CitySense Technologies
- Provided SaaS analytics services to water utilities to reduce lost revenue.
- Built most popular product, which forecasted resource usage and identified deviations in order to pinpoint equipment degradation.
- Built an MVP and beta app, launched in three pilot cities.
- Won third place at the Penn Wharton Startup Competition ($35,000), Summer Venture Award ($10,000), and Innovation Fund ($1,500).
Technologies: Amazon Web Services (AWS), Elm, JavaScript, RStudio Shiny, R, Leadership, Data Science, Data Analytics, Data Visualization, Forecasting, Predictive Analytics, Data Engineering, System Modeling, Data Scientist, Time Series Analysis, Statistics, ROI, Time Series Data, Time Series Forecasting, Time Series
Senior Product Manager (MBA Intern), US Marketplace
2017 - 2017
Amazon
- Designed and built machine learning models to target grocery and CPG items to fast-growing Amazon shopper segments.
- Led partner teams around the world to implement and refine model, scaled to three international markets.
- Led process by coordinating technical and non-technical teams during scoping, development, and planning for roll-out.
Technologies: SQL, Scala, Data Science, Data Analytics, Data Analysis, Predictive Modeling, Big Data, ROI, Forecasting, Predictive Analytics, Data Scientist, Statistics
Product Manager (Earlier roles: business manager, senior business analyst)
2013 - 2016
Capital One
- Led acquisitions of high-spending consumers across the company’s flagship products, Venture and Quicksilver.
- Created an innovative model connecting the effects of offline and online marketing. Obtained a $10 million testing budget to conduct full analysis. Led a small team in the analysis of results.
- Delivered learnings that drive millions in annual value to the CEO and Board. Developed product strategy for market-leading cash rewards card, Quicksilver, growing new customers through digital channels by 40% annually.
- Designed and launched multi-million-dollar campaigns to acquire customers and build brand value in high-impact markets, coordinating a half-dozen internal and external teams. Promoted < nine months after joining the team.
- Oversaw credit card loss forecasting using advanced financial models in multi-billion-dollar credit portfolios.
- Managed biannual stress test of $70 billion in card loans, coordinating the process across 15 people, and producing whitepaper for the Federal Reserve.
Technologies: Microsoft Excel, Visual Basic for Applications (VBA), Python, SQL, SAS, Data Science, Data Analytics, Data Analysis, Predictive Modeling, Data Visualization, Big Data, Pricing Models, Forecasting, Predictive Analytics, System Modeling, Marketing Mix Modeling, Data Scientist, Media Mix Modeling, Time Series Analysis, Statistics, Marketing Science, ARIMAX, Time Series Data, Time Series Forecasting, Marketing Mix, Multi-touch Attribution, Time Series, Google Ads, Econometrics, Meta Ads
Statistical Modeling Analyst
2012 - 2012
Obama for America
- Developed finely tuned models of voter turnout and candidate support in 2012 battleground states.
- Mined massive voter-level datasets with >1,000 data fields (demographics, voting history, household info, 3rd-party data).
- Discovered prediction discrepancies and created new models which overcame poor state data in key variables (e.g. age, party registration).
Technologies: Microsoft Excel, SQL, STATA, Data Science, Predictive Modeling, Forecasting, Predictive Analytics, Data Scientist, Bayesian Statistics, Statistics, Bayesian Inference & Modeling, Marketing Science
Project History
Topic Modeling for Sales Intelligence Platform
Built an end-to-end system for modeling news article topics for hud.ai, an AI-enabled sales intelligence platform. Led the roadmap, development, deployment, and maintenance of the model, ensuring efficient operation for hundreds of thousands of articles.
Executed the following:
• Conducted user interviews to qualify needs and scope project
• Sourced training data
• Cleaned and preprocessed data
• Developed and iterated on topic hierarchy
• Built, validated, evaluated models, choosing gradient-boosted decision tree approach based on sentence-vectorized embeddings
• Dockerized models for serving at an API endpoint
• Built new data tables and API logic to score hundreds of thousands of articles and store scores in RDS and Elasticsearch
• Updated UI/UX to incorporate topic models, and fine-tuned through additional user interviews
Executed the following:
• Conducted user interviews to qualify needs and scope project
• Sourced training data
• Cleaned and preprocessed data
• Developed and iterated on topic hierarchy
• Built, validated, evaluated models, choosing gradient-boosted decision tree approach based on sentence-vectorized embeddings
• Dockerized models for serving at an API endpoint
• Built new data tables and API logic to score hundreds of thousands of articles and store scores in RDS and Elasticsearch
• Updated UI/UX to incorporate topic models, and fine-tuned through additional user interviews
Education
2016 - 2018
Master of Business Administration Degree in Management
The Wharton School - Philadelphia, Pennsylvania, USA
2006 - 2010
Bachelor's Degree in Mathematics
Williams College - Williamstown, Massachusetts, USA
Skills
Libraries/APIs
Node.js, Scikit-learn, TensorFlow, Vue
Tools
Jupyter, Microsoft Excel, ARIMAX, Tableau, STATA, MATLAB
Languages
Python, SQL, JavaScript, R, Excel VBA, Java, SAS, Visual Basic for Applications (VBA), Elm, Scala
Storage
Databases, PostgreSQL, MySQL, Data Pipelines, Elasticsearch
Paradigms
Serverless Architecture, ETL
Platforms
Amazon Web Services (AWS), Docker, Google Ads
Frameworks
RStudio Shiny, Django, Spark
Other
Natural Language Processing (NLP), Predictive Modeling, Machine Learning, Data Visualization, Time Series Analysis, Statistical Forecasting, Data Analysis, Data Analytics, Analytics, Marketing Analytics, Data Science, Statistics, Data Reporting, Generative Pre-trained Transformers (GPT), Big Data, ROI, Executive Consulting, Web Scraping, Forecasting, Predictive Analytics, Data Engineering, Marketing Mix Modeling, Data Scientist, Media Mix Modeling, Bayesian Inference & Modeling, Marketing Science, Time Series Data, Time Series Forecasting, Marketing Mix, Multi-touch Attribution, Time Series, Applied Mathematics, Financial Modeling, Financial Forecasting, Artificial Intelligence (AI), Leadership, Pricing Models, Large Language Models (LLMs), System Modeling, Bayesian Statistics, Google Analytics 4 (GA4), CRM, Econometrics, Serverless, OpenAI, Meta Ads
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