Principal Applied Scientist – User Modeling
Employment Information
Report this job
Job expired or something wrong with this job?
Job Description
Principal Applied Scientist building user-modeling and reinforcement-learning systems for Zillow’s real estate platform. Developing LLM post-training, reward models, and online evaluation for home-shopping agents.
Responsibilities:
- Build user world models that help agents understand each shopper’s journey, goals, and how actions affect outcomes
- Own LLM post-training pipelines, including SFT, DPO, and reinforcement fine-tuning (RFT/GRPO), end-to-end on GPU infrastructure
- Build and train multi-category reward models (PRMs) that emit scalar signals from contrastive preference pairs
- Design on-policy and online assessment using LLM-as-a-Judge frameworks to score live agent trajectories
- Translate offline evaluation rubrics into generalizable reward functions for arbitrary production traces
- Drive complex, ambiguous work end-to-end in collaboration with product, engineering, science, platform, and data teams
- Provide technical leadership and mentorship
- Translate state-of-the-art AI research into production impact for Zillow’s home-shopping experiences
Requirements:
- PhD in Computer Science, Statistics, Economics, Machine Learning, or a related quantitative field, with depth in reinforcement learning or causal inference
- Hands-on experience modeling user behavior at scale using sequence models over event streams, sessions, or trajectories
- Experience predicting user intent or long-term outcomes
- Practical depth in causal inference, including propensity scoring, treatment-effect estimation, and off-policy evaluation, or reinforcement learning applied to real sequential decision problems
- Ability to independently scope and solve ambiguous problems end-to-end
- Ability to provide technical leadership to scientists and MLEs
- Working proficiency in Python and ML frameworks such as PyTorch or TensorFlow
- Ability to run experiments and read, review, and debug code
- Background in economics or econometrics, such as demand modeling or consumer choice
- Published work in RL, causal inference, survival analysis, or user modeling/simulation
- Experience with generative sequence models or conditional language generation for behavioral/conversational simulation
- Experience with rare-event modeling and probability calibration at scale
- Familiarity with two-sided marketplaces, real estate, or long-horizon consumer journeys
Benefits:
- Equity awards based on factors such as experience, performance and location
- Remote work from a physical location of choice within the eligible U.S. locations
- Flexible work through Cloud HQ
- Equal employment opportunity and accommodation support
Similar Jobs
LLM Research Scientist – Pre-training, Computer Vision, Adversarial Robustness
LLM research scientist training robust vision and language models for Mercor’s frontier AI projects. Developing efficient, adversarially robust, and multilingual machine learning systems.
Staff Applied Scientist
Staff Applied Scientist improving machine learning models for Upstart’s AI lending marketplace. Researching predictive performance and deploying reliable unsecured credit decisioning solutions.
LLM Research Scientist – Pre-training, Computer Vision, Adversarial Robustness
LLM research scientist training and improving robust vision and language models for Mercor’s frontier AI lab partners. Conducting empirical research across pre-training, computer vision, and adversarial robustness.
Master's Research Fellow – Conversational AI and Voice Analysis
Mestre pesquisando IA conversacional e análise de voz para projeto de inovação do Itaú. Avaliando modelos, áudio, NLP e agentes de IA para evolução de produtos.
Senior Research Scientist
Senior Research Scientist leading rigorous health services research, evaluation, and policy studies for government healthcare agencies and private clients. Translating evidence into actionable recommendations and publications.
Research Assistant Intern
Part-time remote Research Assistant Intern supporting Population Council reproductive health product research. Assisting with data collection, analysis, literature reviews, IRB files, manuscripts, and reports.
Research Scientist, Benchmarks & Evals
Research Scientist building benchmarks and evaluations for Kled’s opt-in human data network. Measuring how its data improves frontier AI image, video, and document models.
Senior Principal Scientist – US Regulatory Innovation
Senior Principal Scientist shaping US regulatory strategy for Dechra’s veterinary drugs and biologics. Guiding FDA/USDA submissions, product approvals, and regulatory innovation.
Senior Principal Scientist, Regulatory Liaison
Senior Principal Scientist leading global regulatory strategies for Merck’s immunology drug and biologic programs. Guiding submissions, health-authority interactions, labeling, and product approvals worldwide.
PhD Research Fellow – Computing, Engineering, Applied Mathematics
Bolsista doutor pesquisando GraphRAG, RAG e agentes de IA para o projeto de inovação do Instituto Itaú. Desenvolvendo protótipos semânticos e mecanismos de avaliação e segurança.
PhD Research Fellow, Computer Science, Engineering, Applied Mathematics
Bolsista doutor pesquisando GraphRAG, RAG e agentes inteligentes. Desenvolvendo protótipos e mecanismos de avaliação para projeto de inovação do Instituto Itaú de Ciência, Tecnologia e Inovação.
Research Fellow – Workforce Intelligence
Research Fellow analyzing construction labor markets, compensation, and workforce data. Supporting workforce intelligence reports, dashboards, methodologies, and operational planning systems.
Senior Researcher
Senior Researcher leading mixed-methods research and mentoring teams at Ad Hoc, a technology company building digital services for government agencies. Influencing research strategy, stakeholder decisions, and product outcomes.
Master’s Research Fellow – Computational Memory, Cognitive CRM, Intelligent Agents
Bolsista mestre pesquisando memória computacional, RAG temporal e agentes inteligentes no Instituto Itaú de Ciência, Tecnologia e Inovação. Desenvolvendo protótipos e métricas para IA generativa fundamentada.
Research Assistant – Student Worker
Student Research Assistant supporting National University research on women of color Marriage and Family Therapists. Assisting with qualitative data collection, coding, documentation, and scholarly materials.
Senior Research Scientist – Architectures Research
Senior Research Scientist developing efficient model architectures for Nebius’s AI cloud platform. Advancing attention, memory, reasoning, and inference methods through frontier applied research.
Research Assistant – Senior, Early Childhood
Research Assistant supporting Child Trends’ early childhood social science research projects. Collecting, analyzing, and organizing data for research, evaluation, and policy projects.
Senior Research Scientist, Executive Engagement & Insights
Senior Research Scientist leading applied research for Syndio’s pay governance and compensation intelligence platform. Combining proprietary pay data with labor-market data to inform executives, products, and customers.
LLM Research Scientist – Pre-training, Computer Vision, Adversarial Robustness
LLM research scientist training and improving vision and language models for Mercor’s AI lab and enterprise partners. Focusing on adversarial robustness, computer vision, generative modeling, and multilingual pre-training.
LLM Research Scientist – Pre-training, Computer Vision, Adversarial Robustness
LLM research scientist training and improving frontier AI models for vision, language, and adversarial robustness. Conducting empirical research and optimizing models under data, compute, size, and latency constraints.