Junior Data Scientist

Your job in a nutshell

You build data science solutions from raw data to production. You create impact with insights that help our stores, customers, and colleagues make better decisions. This is how you turn data into value and customers into fans.

What are we doing it for?

We want to make smarter, faster, and more customer centric decisions every day. Your analyses and models strengthen our stores, improve processes, and help us delight more customers with sharp prices, full shelves and the best shopping experience.

Your new team

As a Data Scientist, you are part of an enthusiastic, international team of around 15 colleagues. You will report to Wendell Kuling. The team culture is collaborative, entrepreneurial, committed to delivering value, and always focused on learning and continuous improvement.

Who do you work with?

You work closely with colleagues across multiple departments, including end users, Data Analysts, and business Consultants, as well as IT engineers. Together you build the best data products that help turn even more customers into fans.

These will be your challenges

From day one, you work on challenging projects that test both your analytical and interpersonal skills. These projects can span the entire Jumbo organization—from logistics to marketing, and from store formula to purchasing. You build data science products from start (raw data) to finish (production ready models). Easily 50% of your time goes into data preparation, exploration, advanced analysis, and even some BI, so it’s important you enjoy that as much as Machine Learning and building AI Agents. We focus on outcomes, not output: customers become fans through better decisions based on the insights you uncover.

Your responsibilities:

• Analyze large datasets to uncover insights that improve decision making in stores, online, and in the supply chain.
• Build predictive models that improve forecasting for inventory, product demand, and customer behavior.
• Explore commercial opportunities by analyzing pricing, promotion, and assortment data.
• Develop data agents, dashboards, and automated reports that enable colleagues to use your data science products daily.
• Improve data quality by checking data flows, identifying issues, and resolving them.
• Test, optimize, and implement machine learning models in our production environment.
• Translate complex analyses into clear and actionable recommendations for colleagues outside Data Science.
• Deliver direct business impact with your models, such as reducing waste, improving availability, or increasing customer satisfaction.

A day in the life of a Junior Data Scientist at Jumbo:

• 09:00 – 11:00: Work in Databricks (PySpark) with our large datasets to improve the model that estimates product substitutability—crucial for selecting the right assortment.
• 11:00 – 12:00: Review the latest results of the machine learning models in your portfolio.
• 12:00 – 12:45: Lunch meeting with your DS&A colleagues in our Foodcafé.
• 13:00 – 15:00: Conduct a peer review of a model developed by a colleague to improve loyalty offers, applying insights to enhance our assortment model.
• 15:00 – 17:00: Attend a workshop focused on improving store layout differentiation through a datadriven approach.

Who are you?

• You hold an MSc or PhD with excellent academic results in Computer Science, Econometrics, Data Science, or other quantitative fields, and have 0–3 years of relevant work experience.
• You have a passion for both Machine Learning and Agentic AI, and a solid understanding of supervised and unsupervised learning methods (RF, LGBM, XGB, Lasso/Ridge, SVD, KNN, ALS, LLMs, etc.), statistics, time series analysis (BSTS, SARIMAX), and agentic frameworks (Langchain/Langgraph, PydanticAI, OpenAI, autogen). Knowledge of optimization methods (LP/MILP) is a strong plus.
• You understand that Data Science is constantly evolving, so you have a natural curiosity and willingness to learn both hard and soft skills.
• You prefer delivering code and working data products over PowerPoint slides. Python is required; PySpark is a strong plus. You enjoy building data tools in Power BI. Experience with Databricks is a strong plus. SQL and R are nice-to-haves.
• You have strong communication and collaboration skills: you can clearly explain the “so what” (and sometimes the “why”) behind a model recommendation. You guide end users at the pace that matches the possibilities and limitations of your models.
• Although proficiency in Dutch is a plus, it is not required.

What do you get from us?

• A gross salary between €3.900 and €5.100 per month (based on 40 hours).
• An annual bonus of max 5% of your annual salary, based on organizational goals.
• 30 days of paid holiday (with the opportunity to buy or sell days of paid holiday) and 8% holiday allowance. You build up a pension through participation in the Pension Fund for the Food Industry.
• Travel allowance of €0.21 per kilometre (up to 35 km one way). We enjoy working together at the office, but partial remote work is also possible.
• Room for entrepreneurship, growth and development. Not only in your job but also through our Jumbo Academy, online training through GoodHabitz and with a training budget.
• Daily fresh lunch in our Foodcafé, good coffee and fresh fruit. You can sport daily at our own Jumbo Gym for a small fee.
• Colleague discounts such as 10% off your groceries (up to €325 per year), participation in our collective health insurance or discounts through Benefits at Work.

Want to know more about our employment conditions? Click here.

Why Jumbo?

"What's for dinner today?" You hear that question every day. And in your job at Jumbo, you help answer it. Working at Jumbo means working with people. A place where you feel at home, can be yourself, and where we work together toward shared goals. Your ideas to make customers, stores, and colleagues happy are more than welcome here. We believe our Jumbo colleagues make the difference: through who they are, what they do, and how they do it: with commitment, enthusiasm, and sometimes by doing things just a little differently. And we promise you: no two days are the same at Jumbo. There's plenty of room to learn and grow, both professionally and personally. So, what are you waiting for? Join our Jumbo family! You're very welcome here.

Bart Gerritse +31 6 57458753 bart.gerritse@jumbo.com