Machine Learning Engineer PhD Intern

PayPal has been revolutionizing commerce globally for more than 25 years. The MLE PhD Intern plays a critical role in ensuring PayPal’s adherence to a complex and evolving landscape of local and global regulations by leveraging advanced machine learning and data-driven insights to design innovative solutions that streamline compliance processes and strengthen risk mitigation.

Responsibilities

• Gain hands-on experience working on real-world large language model (LLM) and machine learning projects within the domains of commerce, personalization, recommendation, and user behavior understanding
• Assist in the fine-tuning, evaluation, and deployment of LLMs for tasks such as personalized recommendations, semantic search, and behavioral modeling
• Collaborate with experienced engineers, data scientists, and product experts to translate business requirements into actionable LLM and ML-driven solutions
• Analyze data, build prototypes, and explore new methodologies to improve the effectiveness of personalization and recommendation systems
• Contribute to the development and documentation of LLM training pipelines and model evaluation frameworks, ensuring reproducibility and maintainability
• Present findings and recommendations to stakeholders across the organization, highlighting the business impact of personalization and LLM applications
• Network with talented professionals and gain valuable insights into the world of financial technology, personalization, and applied machine learning

Skills

• Strong understanding of machine learning concepts, algorithms, and techniques (e.g., supervised learning, unsupervised learning, deep learning)
• Familiarity with large language models (e.g., GPT, LLaMA, Mistral) and techniques for fine-tuning, prompt engineering, or embeddings-based retrieval
• Proven ability to work with Python, libraries like NumPy, Pandas, Scikit-learn, TensorFlow, PyTorch, and Hugging Face Transformers
• Experience with data analysis, cleaning, and wrangling
• Excellent communication, collaboration, and problem-solving skills
• A passion for learning and exploring new technologies
• Highly motivated and proactive with a strong work ethic
• Currently pursuing a PhD in Computer Science, Machine Learning, Statistics, or a related field
• Strong theoretical foundation in ML algorithms, optimization, and statistical learning theory
• Demonstrated ability to implement and evaluate ML models using Python and libraries such as NumPy, Pandas, Scikit-learn, TensorFlow, and PyTorch
• Experience conducting independent research, with publications in relevant ML/AI conferences or journals (preferred)
• Excellent communication and collaboration skills, with the ability to present research to both technical and non-technical audiences
• Highly motivated, curious, and proactive in exploring new research directions
• Must be enrolled in a PhD program at an accredited university, returning to studies after the internship
• Must reside in the U.S. during the program
• Must be authorized to work in the U.S. for the duration of the internship
• Experience conducting independent research, with publications in relevant ML/AI conferences or journals

Benefits

• Flexible work environment
• Employee shares options
• Health and life insurance

Company Overview