Senior Staff Data Scientist

About the role

Reddit seeks a Senior Staff Data Scientist to lead the charge in understanding and improving content relevance across its vast network. This role is central to enhancing user experience by ensuring people discover the most engaging communities and information. You will be the primary authority on how Reddit measures and evaluates the quality of its feeds and search results.

Key facts

What you'll do

• Establish the definitive standards for measuring the quality of content ranking, search, and recommendations within a dynamic community environment.
• Create frameworks for evaluating ranking and recommendation systems using offline metrics, including developing proxy measures that predict long-term user engagement and satisfaction.
• Design and analyze experiments to assess the impact of relevance features, accounting for unique platform dynamics like community spillover effects and long-term content supply impacts.
• Identify opportunities to unlock new product insights through advanced measurement and analysis, particularly concerning content quality, search intent, and personalization effectiveness.
• Collaborate closely with Machine Learning Engineers and product teams to translate model performance into tangible user benefits.
• Influence the strategic direction of Feeds and Search by presenting clear, data-backed recommendations to senior leadership.
• Mentor other data scientists, enhancing organizational expertise in relevance evaluation, experimentation for ranking systems, causal reasoning, and statistical rigor.
• Share methodological advancements internally and externally to contribute to the broader data science community.

Requirements

• Ph.D. in Statistics, Computer Science, Information Retrieval, Economics, or a related quantitative field with a focus on recommendation systems, ranking, causal inference, or evaluation methodology; OR a Master's degree with equivalent depth of experience.
• For Master's degree holders: 12+ years of industry experience in applied science, data science, or roles focused on relevance/ranking.
• For Ph.D. holders: 8+ years of industry experience in applied science, data science, or roles focused on relevance/ranking.
• Profound expertise in designing and evaluating metrics for ranking and recommendation systems, including offline metrics and counterfactual evaluation.
• Strong grasp of causal inference and experimentation methodologies, with practical experience addressing challenges specific to ranking systems like novelty effects, position bias, long-run impact estimation, and ecosystem-level effects.
• Experience defining and validating quality metrics for content ranking, search, or recommendations at scale.
• Solid theoretical understanding of experimental design, including power analysis, variance reduction, and sequential testing as applied to relevance experiments.
• Expert proficiency in SQL and strong command of R and/or Python for statistical analysis.
• Proven ability to influence product and organizational strategy through data-driven insights on content quality and user experience.
• Excellent communication skills, capable of explaining complex statistical and ML concepts to both technical and non-technical senior stakeholders.
• Experience mentoring data scientists and building team capabilities in relevance evaluation and experimentation.
• Comfortable working in fast-paced, innovative environments with a focus on execution.

Nice to have

• Published research or industry contributions in recommendation systems or causal inference for ranking.
• Experience with social network platforms or user-generated content platforms where community dynamics present complex relevance and experimentation challenges.

Skills & tools

• SQL
• R
• Python

Practical notes

• Base salary range: $232,500 - $325,500 USD.
• Eligible for equity in the form of restricted stock units.
• Comprehensive US-based benefits include: Medical, dental, and vision insurance, 401(k) with employer match, generous paid time off, family planning support, gender-affirming care, mental health and coaching benefits, and parental leave.
• Interviews may be recorded, transcribed, and summarized by AI; candidates will have the option to opt out.
• Reddit is an equal opportunity employer committed to diversity and inclusion. Reasonable accommodations are available for individuals with disabilities.