Data scientist - Recommerce - Causal inference (F/N/M)

leboncoin is France's leading classifieds platform for peer-to-peer transactions, the market leader in real estate and automotive, and a key player in jobs and holiday rentals. Every month, leboncoin is the go-to platform for 28 million French users who value the breadth of its listings and the simplicity of everyday transactions.

At leboncoin, data is at the heart of every decision. By joining the Recommerce Data Analytics  team, you will directly contribute to accelerating the growth of the Recommerce business through analytical and predictive models with a strong business impact.

Your scope: Recommerce The Recommerce scope covers all physical goods bought and shipped via leboncoin (electronics, books, cultural products, home décor, etc.). It is a fast-growing market, rooted in circular economy trends, with strong challenges around profitability, user retention, and logistics optimisation.

The key challenges of this scope are:

• Measuring and maximising the long-term value (LTV) of buyers and sellers
• Understanding the true incrementality of marketing, CRM and promotional actions
• Predicting and optimising logistics costs and delivery times

You will join a Data Analytics team of 8+ Data Analysts and 2 Data Engineers, working closely together on the Recommerce scope.

• Minimum 6 years of experience as a Data Scientist
• Strong expertise in causal inference and experimentation (A/B test design and analysis)
• Proficiency in Python and SQL; hands-on experience with Databricks and Airflow is a plus
• Experience in predictive modelling (ML, segmentation, time series)
• Ability to translate complex results into actionable recommendations for non-technical stakeholders
• Curiosity and drive for concrete business impact
• Autonomy, rigour and strong analytical mindset
• Fluent in English
• Fluent in French

Incrementality measurement and causal analysis :• Design methodologies to measure the incrementality of promotional initiatives

• Conduct exploratory and correlation analyses on historical data (revenue, GMV, supply/demand indicators…) to inform re-pricing and promotional initiatives decisions
• Strengthen performance measurement with forecasting models and robust baseline definition

LTV (Lifetime Value) and segmentation :• Identify highest-LTV segments and its drivers to improve prioritization of CRM campaigns and promotional initiatives

• Compute CAC/LTV for CRM
• Introduce and test a trajectory-based user segmentation to react quickly to decline and churn in the top buyer and seller segments

Prototyping and Discovery :

• Collaborate with Product MLE and DS on prototyping IA features (weight suggestion, delivery times…)
• Run exploratory analysis around improving sell-through (= time between an ad listing and its sale)

• Company health insurance
• 50% reimbursement of your public transport pass
• 25 days of annual leave and 12 RTT days (additional rest days)
• A Swile meal card worth €9 per day

At leboncoin, we believe that diversity in backgrounds, experiences and perspectives is essential. This commitment is reflected in our recruitment process: we assess every application solely on the basis of skills, experience and motivation, without any form of discrimination. If you need any specific accommodations during the recruitment process, please let us know. We’ll be happy to support you.