Senior Data Science Analyst – Recommendation Systems & A/B Testing Lead at arenaflex (Boston, Full‑Time, $24/hr)

About arenaflex – Pioneering the Future of E‑Commerce

arenaflex is a global leader in online retail, delivering millions of products to customers worldwide through a seamless blend of technology, design, and logistics. Our mission is to inspire shoppers to discover the perfect items for their homes, while empowering a diverse community of merchants, creators, and engineers to innovate at scale. With a data‑driven culture at its core, arenaflex invests heavily in cutting‑edge analytics, artificial intelligence, and experimentation to continuously refine the shopping experience. As part of our Boston hub, you will join a vibrant, fast‑growing team that thrives on curiosity, collaboration, and impact.

Why This Role Matters

The Senior Data Science Analyst position sits at the heart of arenaflex’s Recommendation & Search team. In this role, you will translate massive, complex datasets into actionable insights that shape the next generation of product recommendation algorithms. Your work will directly influence how millions of customers discover items, increasing engagement, conversion, and loyalty. By partnering with product managers, engineers, and designers, you will help define the strategic roadmap for recommendation systems, ensuring they are both innovative and grounded in rigorous scientific methodology.

Key Responsibilities

• Design, implement, and evaluate A/B experiments for new recommendation algorithms, ensuring statistical rigor and clear business impact.
• Develop and maintain KPI dashboards that monitor model health, anomaly detection, and performance trends across the recommendation pipeline.
• Conduct exploratory data analysis (EDA) to uncover hidden patterns, segment customers, and generate hypotheses for product improvements.
• Build and iterate on internal tooling, such as a QA framework that simulates model behavior before live deployment, reducing risk and accelerating iteration cycles.
• Collaborate closely with cross‑functional partners—product managers, data engineers, ML engineers, and UX designers—to translate business goals into data‑driven solutions.
• Communicate findings and recommendations to senior leadership through clear visualizations, storytelling, and concise executive summaries.
• Mentor junior analysts and data scientists, fostering a culture of continuous learning and best‑practice sharing.
• Stay ahead of industry trends in recommendation systems, causal inference, and machine learning, bringing fresh ideas to the team.

Essential Qualifications

• Bachelor’s degree in Computer Science, Statistics, Mathematics, Engineering, or a related quantitative discipline (Master’s or Ph.D. preferred).
• 5+ years of hands‑on experience in data science, analytics, or research roles within an e‑commerce or technology‑driven environment.
• Deep expertise in SQL—query optimization, data warehousing concepts, and familiarity with platforms such as Vertica, Hive, or Snowflake.
• Advanced proficiency in Python, including libraries such as Pandas, NumPy, Scikit‑learn, Matplotlib, and Jupyter notebooks.
• Proven track record designing, executing, and interpreting A/B tests that drive product decisions.
• Experience applying machine learning models (e.g., decision trees, random forests, deep learning) to solve real‑world business problems.
• Strong analytical mindset with the ability to translate complex data into clear, actionable business insights.
• Excellent written and verbal communication skills, with a collaborative, team‑first attitude.

Preferred Qualifications & Nice‑to‑Haves

• Graduate degree (M.S. or Ph.D.) in a quantitative field.
• Hands‑on experience with big‑data processing frameworks such as Spark or Hadoop.
• Familiarity with experimentation platforms (e.g., Optimizely, Google Optimize) and causal inference techniques.
• Exposure to cloud environments (AWS, GCP, Azure) and containerization (Docker, Kubernetes).
• Background in recommendation system architectures, collaborative filtering, or content‑based methods.
• Demonstrated ability to lead cross‑functional projects from ideation to production.

Core Skills & Competencies

• Statistical Rigor: Mastery of hypothesis testing, confidence intervals, and power analysis.
• Data Engineering Acumen: Ability to extract, transform, and load (ETL) large datasets efficiently.
• Machine Learning Insight: Understanding of model selection, feature engineering, and model monitoring.
• Product Sense: Keen awareness of how data insights translate into product features and user experience.
• Communication: Skillful storytelling with data visualizations that resonate with both technical and non‑technical audiences.
• Collaboration: Proactive partnership with engineers, designers, and product owners to align on goals.
• Adaptability: Thriving in a fast‑paced environment where priorities shift based on business needs.

Career Growth & Learning Opportunities

arenaflex invests heavily in the professional development of its employees. As a Senior Data Science Analyst, you will have access to:

• Annual learning stipend for conferences, certifications, or advanced coursework.
• Mentorship programs pairing you with senior leaders in data science and product strategy.
• Opportunities to lead high‑visibility projects that influence company‑wide product roadmaps.
• Cross‑team rotations that broaden your expertise across recommendation, search, and personalization domains.
• Regular internal hackathons and innovation days to experiment with emerging technologies.

Work Environment & Culture at arenaflex

Our Boston office is a collaborative hub where ideas flow freely. We champion a culture of inclusion, curiosity, and continuous improvement. Highlights include:

• Flexible work hours and hybrid remote options to support work‑life balance.
• Open‑plan spaces designed for teamwork, as well as quiet zones for focused analysis.
• Diverse employee resource groups that celebrate different backgrounds and perspectives.
• Regular social events, wellness programs, and volunteer initiatives that foster community.
• A commitment to accessibility—arenaflex provides reasonable accommodations for candidates with disabilities throughout the hiring process and employment lifecycle.

Compensation, Perks & Benefits

arenaflex offers a competitive compensation package that reflects your expertise and impact. While the base hourly rate for this role is $24/hr, you can also expect:

• Performance‑based bonuses tied to project outcomes and business metrics.
• Comprehensive health, dental, and vision coverage for you and your dependents.
• Retirement savings plans with company matching contributions.
• Generous paid time off, parental leave, and holidays.
• Employee stock purchase program and equity grants for long‑term wealth building.
• Wellness stipend, on‑site fitness facilities, and mental‑health resources.
• Professional development budget and tuition reimbursement.

How to Apply

If you are a data‑driven problem‑solver with a passion for building recommendation systems that delight customers, we want to hear from you. Join arenaflex’s dynamic Boston team and help shape the future of online shopping.

Apply Now – Submit Your Resume and Cover Letter

Equal Opportunity & Accessibility Statement

arenaflex is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees. We provide reasonable accommodations for qualified individuals with disabilities. If you require assistance or an accommodation during the application process, please let us know.