Aymen Jaffry, Machine Learning Developer in Paris, France
Aymen Jaffry

Machine Learning Developer in Paris, France

Member since May 23, 2014
Aymen has worked for 6+ years as a data scientist, machine learning engineer, and consultant. He has worked in many industries, including finance, advertising, and online marketplaces. He greatly enjoys using machine learning and statistics to build state-of-the-art and efficient solutions. He holds an M.S. in Computational Engineering from Harvard University and a Master in Applied/Theoretical Mathematics from Ecole Centrale Paris.
Aymen is now available for hire


  • Yieldmo
    Python, Java, SQL, Sklearn, Reinforcement Learning, Online Models
  • Yieldmo
    Python, Java, SQL, Sklearn, Reinforcement Learning, Online Models
  • Catalant Technologies
    Python, R, SQL, Recommender Systems, Graph Theory



Paris, France



Preferred Environment

OS X, Python, Jupyter, Atom, Git

The most amazing...

...thing I've built is a system using machine learning and statistics to predict 911 calls at the street level in the Boston area.


  • Machine Learning Consultant

    2016 - 2018
    • Developed an innovative classification algorithm, using online learning, to predict the advertisers’ conversion rates and automate bidding strategies.
    Technologies: Python, Java, SQL, Sklearn, Reinforcement Learning, Online Models
  • Data Scientist, Ad Serving Team

    2014 - 2016
    • Worked on display advertising, applying machine learning and reinforcement learning techniques to the problem of predicting click-through-rate.
    • Implemented a dynamic A/B testing platform that allowed thousands of A/B tests to run in parallel.
    • Used Bayesian Statistics and Thompson Sampling to redesign second-price auction rules and A/B testing decisioning.
    Technologies: Python, Java, SQL, Sklearn, Reinforcement Learning, Online Models
  • Machine Learning Consultant

    2013 - 2014
    Catalant Technologies
    • Built the first version of the matching engine from scratch using graph theory. This system recommends newly posted projects to MBA students on the platform and vice-versa.
    • Ran market analysis to identify lags between offer (projects) and demand (MBA students' expertises).
    Technologies: Python, R, SQL, Recommender Systems, Graph Theory
  • Consultant in the Statistical Learning Team

    2011 - 2012
    • Developed a system in R recommending the best marketing means to reach each new customer on the website.
    • Conducted analysis to build customer groups using unsupervised and supervised learning techniques.
    Technologies: R, Python, Sklearn, Unsupervised Learning, PCA, Clustering
  • Assistant Trader and Structurer

    2010 - 2011
    UBS Investment Bank
    • Built a prototype tool that dynamically rebuilt a collateral portfolio using the risk of default analysis.
    • Assisted the secured funding team in creating new products by running forecast tests and coming up with.
    • Completed ROI and value propositions.
    • Priced primary/secondary quotes and hedged currency strategies.
    Technologies: R, VBA, Backtests, Time Series Analysis, Risk of Default
  • Assistant Researcher

    2010 - 2010
    Cornell University, CFEM
    • Implemented a multi-agent system based on Ask/Bid and PnL data analysis simulating a stable financial market.
    • Worked under the supervision of Dr. Sasha Stoikov, Head of Research at CFEM.
    Technologies: Java, C++, Reinforcement Learning


  • Languages

    SQL, Python, Java, R, C++, J
  • Libraries/APIs

    Sklearn, Scikit-learn, Pandas, Matplotlib, Spark ML, TensorFlow, Keras, REST APIs
  • Tools

    Jupyter, IPython, Git, Apache Airflow
  • Paradigms

    Data Science, Object-oriented Programming (OOP)
  • Platforms

    Eclipse, MacOS, Linux, Docker
  • Industry Expertise

  • Storage

    MySQL, AWS S3
  • Other

    A/B Testing, Mathematics, Analytics, Big Data, Bayesian Statistics, Advertising, Machine Learning, Vowpal Wabbit, Google BigQuery, Unsupervised Learning, Deep Learning, Natural Language Processing (NLP), Reinforcement Learning, Finance
  • Frameworks

    Apache Spark


  • Master of Science degree in Computational Science and Engineering
    2013 - 2014
    Harvard University - Massachusetts
  • Master's degree in Applied and Theoretical Mathematics
    2009 - 2013
    Ecole Centrale Paris - Paris, France
  • Bachelor of Science degree in Mathematics, Physics
    2006 - 2009
    Marcelin Berthelot Preparatory Classes - Paris, France

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