Data Science Data Science Senior Data Scientist

Titan OS), the Barcelona-based technology, entertainment, and advertising company, is looking for you We are looking for a Senior Data Scientist to lead the development of predictive audience models for Titan OS, turning smaller seed and observed datasets into robust predictions of much larger customer populations for Connected TV advertising. This is a deeply technical role focused on statistics, sampling theory and machine learning, with a strong emphasis on representativeness, selection bias, population extrapolation and uncertainty.
You will combine Titan OS first-party data with seed audiences and population-level datasets, owning the methodology from research and experimentation through validation, productionisation and model monitoring. Working closely with Data Engineering, Product, Commercial and Advertising teams, you'll be a senior technical voice responsible for challenging assumptions, communicating uncertainty and setting rigorous modelling standards with direct commercial impact.
Create robust behavioural and contextual features from large-scale event data while preventing target leakage and instability.
Diagnose selection bias, coverage gaps and covariate shift, and communicate uncertainty in audience estimates.
Measure lift, precision/recall, calibration and stability using holdouts, temporal/geographic tests and observed campaign outcomes.
Move successful models into scalable pipelines with versioning, drift detection, monitoring and retraining.
Partner with Product, Commercial and Engineering teams while setting rigorous modelling standards across the Data team.
What makes you a great fit:8+ years of professional experience in Data Science, Applied Statistics, Quantitative Research, Econometrics or a closely related field.
Hands?on ML lookalike experience using seed audiences, CRM/customer samples or known converters with propensity, classification, similarity/ranking or positive?Strong model validation skills including lift/gains, precision@K/recall@K, probability calibration, A/B testing, stability and drift monitoring.
Advanced Python & SQL skills with scikit-learn, pandas/NumPy and experience with large?scale cloud data platforms and production ML/MLOps are highly desirable.a PhD is advantageous but not required.growth company in the early stages to help shape a product/business that will impact millions. #