Senior Data Scientist (Bayesian Modelling)

• Select and build Bayesian, frequentist, or machine learning methods to improve flagship measurement platforms
• Build hierarchical, time-series, and audience models using PyMC, Stan, or NumPyro
• Define team best practices for priors, diagnostics, posterior checks, and scalable inference
• Mentor junior and mid-level data scientists through code reviews, technical sessions, and shared best practices
• Translate probabilistic outputs into clear, actionable business insights for client stakeholders

Technologies:

• AWS
• Machine Learning
• Python
• SQL
• pandas
• Cloud

More:

We power advertising measurement for some of the biggest brands in the US. We are rebuilding our flagship products around Bayesian frameworks, moving beyond legacy frequentist methods to process tens of millions of data points with greater accuracy and speed. As our Senior Data Scientist, you will set technical standards across our growing 25-person UK team, own core models, choose methods suited to the work, and help guide major commercial decisions.

• Practical experience with hierarchical models, MCMC, and variational methods, with hands-on experience using PyMC, Stan, or NumPyro
• Strong proficiency in Python, SQL, and pandas; experience with Polars or AWS is a plus
• Five years of data science experience; PhD and postdoctoral work count toward this total
• Ability to explain complex probabilistic modeling and connect it to commercial decision-making