Principal Applied Scientist / Lounge by Zalando (all genders)

Role: Principal Applied Scientist at Zalando Lounge, fostering data-driven decision-making by designing experimentation frameworks and analyzing complex A/B tests. Expert in causal inference and statistical modelling. Collaborates with fellow economists and cross-functional teams (applied scientists, data analysts, product managers, software developers, data engineers, commercial stakeholders). Responsibilities: - Designing experimentation frameworks in new areas (KPIs, unit of randomization, statistical power analysis, variance reduction). - Designing and executing experiments in complex cases (e.g., SUTVA violations, test vs. long-term effect relationships). - Identifying causal relationships using observational data to inform product development. - Applying economic modeling and first-principles thinking to guide business decisions. - Providing egoless, constructive scientific feedback to peers and coaching junior colleagues. - Setting broad scientific roadmaps across the division, requiring a significant industry track record and scientific leadership experience. Qualifications: - Ph.D. in Economics with emphasis on quantitative research methods. - At least two years of professional experience. - Expertise in experimentation. - Experience with quasi-experimental research methods (e.g., DML, causal forest, difference-in-differences). - Strong general scientific problem-solving skills. - Proficiency in Python and knowledge of SQL. - Regular use of AI-based analytical tools and a mindset of constant exploration of new developments. - Ability to communicate analytical insights to both technical and non-technical audiences. What We Offer: - 27 days of holiday a year to start for full-time employees (+1 day for every calendar year up to 30 days). - 2 paid volunteering days a year. - Hybrid working model with up to 60% remote per week, actual practice determined by each team. - Work from abroad for up to 30 working days a year. - Employee shares program. - 40% off fashion and beauty products sold/shipped by Zalando, 30% off Lounge by Zalando, discounts from external partners. - Relocation assistance available (subject to prior agreement). - Family services, including counseling and support. - Health and wellbeing options (including Wellhub, formerly Gympass). - Mental health support and coaching. - Drive your development through our training platform and biannual peer-to-peer review.