Staff Data Scientist - Ads Measurement, Signals, Privacy

Reddit is a community of communities. It’s built on shared interests, passion, and trust, and is home to the most open and authentic conversations on the internet. Every day, Reddit users submit, vote, and comment on the topics they care most about. With 100,000+ active communities and approximately 130 million daily active unique visitors, Reddit is one of the internet’s largest sources of information. For more information, visit www.redditinc.com .

Reddit’s Ads Data Science team is looking for a highly experienced Staff Data Scientist to advance the intelligence powering the advertiser experience on Reddit. In this role, you'll take deep ownership of a high-impact problem space within advertising, specializing in measurement, identity, and signal quality.

This is a high-impact, high-autonomy role where you'll influence strategic direction, set a high technical bar, and drive cross-functional initiatives across one or more critical focus areas in the Ads organization.

Responsibilities:

Design the Future of Ads Identity: Develop/employ probabilistic models for identity resolution. Design the methodology that links on-platform and off-platform actions to maximize addressability while honoring privacy.

Advance Lift Methodologies & Experimentation: Own the statistical rigor behind Reddit’s Brand and Conversion Lift products. Innovate experimental design and develop infrastructure that supports large-scale, high-velocity, low-bias testing for advertisers.

Maximize Signal for Predictive Performance: Define the strategy for new signal sources. You will mathematically quantify the value of these signals and work with modeling teams to incorporate them into predictive models, directly improving bidding efficiency and ROAS.

Define Ground Truth & Evaluation Frameworks: Solve the industry-wide challenge of validating identity and measurement. Design the objective functions and truth sets used to train our models and measure the incremental impact of our identity graph.

Lead Through Cross-Functional and Technical Influence: Collaborate deeply with engineering, product, and sales to align on strategic goals, translate insights into action, and drive execution. Set a high technical bar by mentoring others and championing best practices across modeling, experimentation, and measurement.

Qualifications:

Required:

Advanced degree (Master's or Ph.D.) in Statistics, Mathematics, Physics, Economics, or Operations Research

For M.S. holders: 10+ years of industry experience in applied science or data science roles

For Ph.D. holders: 6+ years of industry experience in applied science or data science roles

Deep understanding of the ads ecosystem

Demonstrated expertise in at least one of the following areas:

Measurement & Experimentation at Scale (with focus on lift and attribution)

Identity Graph Creation & Resolution Methodology and Infrastructure

Predictive Modeling with Signal Loss

Advanced proficiency in statistical programming (Python or R) and SQL.

Experience with machine learning or optimization techniques

Strong understanding of experimental design, causal inference, or A/B testing methodologies

Exceptional problem-solving and communication skills, with a track record of influencing product and engineering partners

Experience working in fast-paced, ambiguous environments with cross-functional teams