Senior Data Scientist
Essentials
Job title: Senior Data Scientist
Location: Romania, remote
Type: employment contract
Offer
Remuneration & work-life balance:
Competitive salary and trust-based working hours.
Private health insurance.
Generous training budget.
2 extraordinary team events (4 days) per year.
Meal benefit.
Communication & trust:
Open, honest and direct communication. Your ideas are welcome!
A feedback meeting every quarter to help us grow together.
We encourage innovation and are open to new ideas that push the boundaries.
Modern working:
Everything you need for your daily work: MacBook, monitor, headphones and more.
Individual training:
One training day per month and a generous training budget for your personal development.
Buddy program:
An experienced team member will support you from day one to help you get started.
Client
Our client creates innovative, user-friendly and modern applications that make lotto accessible to everyone. They truly believe that dreaming and hoping together through lotto empowers life — and now they’re building a brand-new team in Romania.
Role
Build our client understanding of marketing effectiveness: how they measure channel performance, predict valuable users, and turn insights into better decisions on budget, targeting, and personalization.
Your Tasks & Responsibilities
Build predictive models for marketing and user growth use cases, such as LTV, churn risk, propensity to convert, or user segmentation
Support the design and analysis of experiments, holdouts, and A/B tests to understand whether marketing and product actions are creating real impact
Help improve how we measure marketing effectiveness, starting with practical approaches such as channel analysis, attribution, and incrementality tests, and evolving toward more advanced methods over time
Translate model outputs into clear, decision-ready recommendations on budget allocation, channel mix, and audience targeting, with honest trade-offs and uncertainty communicated plainly.
Partner closely with Marketing, UX, Product, and Data colleagues to identify high-impact opportunities and turn ambiguous questions into useful decisions.
Your goals in this role
Within 1 month: Deliver a first working marketing measurement diagnostic or prototype recommendation, such as an attribution readout, channel performance analysis, or budget allocation framework, with documented assumptions and next validation steps.
Within 3 to 4 months: Have at least one predictive model (LTV, churn, or propensity) running on a regular cadence, validated via experimentation and influencing a real marketing decision.
Within 6 months: Operate a repeatable measurement and modelling pipeline, regularly refreshed, monitored, and used by the marketing team to guide budget and targeting decisions.
Your Key Competencies
Must have
Strong applied statistics and machine learning, especially regression, classification, forecasting, experimentation, and uncertainty estimation in business contexts.
Solid experimentation skills: designing tests, choosing the right metrics, and interpreting results without overfitting to noise.
Strong data skills: SQL and Python, feature engineering, working with large datasets in cloud warehouses (e.g. BigQuery).
Ability to work end-to-end: from ambiguous business questions to validated model to clear recommendation.
Clear communication: you can explain model outputs, uncertainty, and trade-offs to non-technical stakeholders.
Nice to have:
Experience with Marketing Mix Modelling or Bayesian methods.
Experience with paid digital channels, CRM, lifecycle, retention marketing, or consumer subscription/app businesses.
Your impact in this role
You contribute to making budget and channel decisions grounded in evidence, not intuition.
You partner across the team to acquiring and retaining users more efficiently by targeting the right people with the right message.
You support faster learning cycles by helping design strong experiments, interpret results accurately, and build on insights over time.
You contribute to building a measurement foundation that scales beyond marketing into other parts of the business.
Your soft skills
- High ownership: ships, measures, iterates—doesn’t stop at “analysis done”.
- Strong stakeholder communication: explains trade-offs, uncertainty, and rollout risks clearly.
- Pragmatic prioritization under ambiguity; focuses on highest ROI levers first.
- Calm, structured execution (production-quality over “clever hacks”).
- Collaborative mindset with Engineering/Data/Marketing/Finance.
Your Background – Education & Experience
- Degree in Statistics, Mathematics, Computer Science, Econometrics, or a related quantitative field, or equivalent demonstrated skill.
- 4+ years of experience in Data Science or Applied ML
Apply today
If you meet the minimum requirements and are interested in applying for this position, please send your details to careers@key-talents.com with “Senior Data Scientist”in the subject line.