Data Scientist

Department: Marketing Effectiveness - Europe

Employment Type: Permanent - Full Time

Location: Sofia, Bulgaria, Hybrid

Key Responsibilities

• Prepare, clean, and quality-check datasets using SQL and Python or R 
• Build and validate statistical models, including regression, machine learning, and forecasting 
• Apply sound statistical thinking, including a working understanding of Bayesian ideas (priors, uncertainty, posterior interpretation) 
• Automate recurring analysis so the team can reuse pipelines, functions, and tools
• Use Git to work with the team’s codebase 
• Document methods and results clearly so others can review, rerun, and present the work 

Skills, Knowledge and Expertise

• 1–2 years in an Analytics or Data Science team 
• Degree in Computer Science, Data Science, Statistics, Mathematics, Economics, or a related quantitative field 
• Strong coding in Python or R (both is a plus) 
• SQL 
• Solid statistics: regression, machine learning fundamentals, and model validation 
• Working understanding of Bayesian methodologies 
• Comfortable with Git 
• Fluent English, written and spoken 
• Intellectually curious, organised, and able to work independently on well-scoped problems 

• Hands-on Bayesian tooling (Stan, PyMC, brms, or similar) 
• Cloud familiarity (AWS, Azure, or GCP) 
• Experience in media, marketing, or marketing-effectiveness work 
• Time series, causal inference, or test design