Data Scientist

Arena Intelligence, Inc.; San Francisco (CA); On-site; Full time

Benefits offered by this job

Competitive compensation

Comprehensive health benefits

Equity aligned to market

Mission-driven team culture

Job summary

A leading AI evaluation platform is seeking a Data Scientist with over 6 years of experience in data science and machine learning analytics. The role involves analyzing large datasets, formulating hypotheses, and collaborating with ML researchers. The ideal candidate will have strong proficiency in Python and tools like Pandas and Spark. Competitive compensation and comprehensive health benefits are offered, alongside the opportunity to work on cutting-edge projects within a mission-driven team.

Qualifications

• 6+ years of experience in data science or ML analytics.
• Strong proficiency in Python with experience in Pandas and Spark.
• Expertise in statistical modeling and causal inference.

Responsibilities

• Analyze large datasets to uncover patterns and causal relationships.
• Formulate and validate hypotheses about data quality and model performance.
• Communicate insights effectively to both technical and non-technical partners.

Skills

Data analysis

Statistical modeling

Causal inference

Python

ML analytics

Tools

Pandas

NumPy

Spark

Job description

About LMArena

LMArena is the open platform for evaluating how AI models perform in the real world. Created by researchers from UC Berkeley’s SkyLab, our mission is to measure and advance the frontier of AI for real-world use.

Millions of people use LMArena each month to explore how frontier systems perform — and we use our community’s feedback to build transparent, rigorous, and human-centered model evaluations. Leading enterprises and AI labs rely on our evaluations to understand real-world reliability, alignment, and impact. Our leaderboards are the gold standard for AI performance — trusted by leaders across the AI community and shaping the global conversation on model reliability and progress.

We’re a team of researchers, engineers, academics, and builders from places like UC Berkeley, Google, Stanford, DeepMind, and Discord. We seek truth, move fast, and value craftsmanship, curiosity, and impact over hierarchy. We’re building a company where thoughtful, curious people from all backgrounds can do their best work. Everyone on our team is a deep expert in their field — our office radiates excellence, energy, and focus.

About the Role

As a Data Scientist you’ll explore and reason about the data that powers millions of AI evaluations each week. You’ll generate and test hypotheses, identify causal relationships, and uncover insights that help us understand how frontier models behave in the real world.

You’ll collaborate with ML researchers and engineers to design experiments, analyze large-scale datasets, and build statistical frameworks that improve the reliability and interpretability of our AI evaluation systems. We are considering candidates who are senior level or higher for this role.

You’ll

• Explore and analyze large, complex datasets to uncover patterns, biases, and causal relationships in model behavior and system performance.
• Formulate hypotheses about data quality, evaluation outcomes, and model performance — then design experiments to validate or refute them.
• Build reproducible analysis pipelines using Python, Pandas, NumPy, and Spark to process and interrogate large-scale data.
• Partner with ML researchers and engineers to design metrics and analyses that evaluate how models perform across domains, prompts, and tasks.
• Develop causal reasoning frameworks and statistical methods that help explain why models behave as they do — not just how well they perform.
• Communicate insights (for example, via blog posts) clearly to technical and non-technical partners, informing both research direction and infrastructure improvements.

You’ll have

• 6+ years of experience in data science, ML analytics, or applied research, preferably in AI, ML, or large-scale data environments.
• Strong proficiency in Python, with deep experience in Pandas, NumPy, and distributed frameworks like Spark.
• Expertise in statistical modeling, causal inference, and experimental design.
• Experience reasoning about data distributions, sample quality, and the effects of data distribution shifts.
• Strong communication skills and the ability to collaborate closely with ML researchers and engineers.
• (Bonus) Background in AI model evaluation.
• (Bonus) Experience working with LLM outputs (for example, LLM-as-a-judge), embeddings, or other large-scale model artifacts.
• (Bonus) Experience with A/B testing.

What we offer

• We offer competitive compensation and equity aligned to the markets where our team members are based. The base salary range will depend on the candidate’s permanent work location.
• Comprehensive health and wellness benefits, including medical, dental, vision, and additional support programs.
• The opportunity to work on cutting-edge AI with a small, mission-driven team
• A culture that values transparency, trust, and community impact

Come help build the space where anyone can explore and help shape the future of AI.

LMArena provides equal employment opportunities (EEO) to all employees and applicants for employment without regard to race, color, religion, sex, national origin, age, disability, genetics, sexual orientation, gender identity, or gender expression. We are committed to a diverse and inclusive workforce and welcome people from all backgrounds, experiences, perspectives, and abilities.