Principal Applied Scientist / Lounge by Zalando (all genders)

Overview

A Principal or Senior Applied Scientist at Zalando Lounge will foster data‑driven decision‑making by designing experimentation frameworks and analysing complex A/B tests, serving as an expert in causal inference and statistical modelling.

In this role you will collaborate with economists, data scientists, product managers, engineers and commercial stakeholders across 13 European countries, contributing to research that informs company strategy and product development.

We are the fastest growing sales channel, generating approximately 15% of the Zalando Group revenue, creating research opportunities in pricing, campaigns and customer experience.

Responsibilities

• Design experimentation frameworks in new areas, focusing on KPIs, units of randomisation, statistical power analysis and variance reduction.
• Design and carry out experiments for complex cases, addressing stable‑unit‑treatment‑value‑assumption violations and non‑trivial relationships between short‑term and long‑term effects.
• Apply quasi‑experimental methods to observational data, establishing causal relationships to inform product development and future experiments.
• Use economic modelling and first‑principles reasoning to guide business decisions.
• Provide constructive scientific feedback to peers and coach junior colleagues.
• Set broad scientific roadmaps across the division and drive industry‑leading work.

Qualifications

• Ph.D. in Economics (or related discipline) with an emphasis on quantitative research methods, plus at least two years of post‑Ph.D. experience.
• Deep expertise in experimentation and quasi‑experimental research methods such as double machine learning and difference‑in‑differences.
• Strong scientific problem‑solving skills and ability to communicate analytical insights to both technical and non‑technical audiences.
• Proficiency in Python and SQL; experience with scikit‑learn, PyTorch, Jupyter, Airflow, DBT, PySpark, Databricks and Git.
• Experience estimating heterogeneous effects such as causal forests and regular use of AI‑based analytical tools.
• Proven track record and scientific leadership experience (required for Principal level).

Inclusive By Design

We encourage applicants who do not meet every requirement; emphasis is placed on research, problem‑solving skills, and contribution potential. Personal details such as photo, age or marital status are not considered. Request accommodations during the hiring process if needed.

Benefits

• 27 days of holiday a year for full‑time employees, plus one additional day per calendar year up to a maximum of 30 days.
• Hybrid working model with up to 60% remote per week.
• Up to 30 working days abroad per year.
• Employee share programme.
• 40% off fashion and beauty products sold and shipped by Zalando, 30% off Lounge products and discounts from external partners.
• Relocation assistance (subject to prior agreement).
• Family services, including counseling and support.
• Health and wellbeing options, including Wellhub (formerly Gympass).
• Mental health support and coaching.
• Training platform and biannual peer‑to‑peer review.

Application Process

All applications must be submitted via the online form. Email applications are not accepted.

Equal Employment Opportunity

Zalando is an equal‑opportunity employer. We support a diverse and inclusive workplace and consider all qualified candidates without regard to age, gender, race, religion, disability, or any other protected characteristic.