Data Scientist Lead Analyst

About the position

As part of Citi’s Financial Crimes and Fraud Prevention - Modeling and Data organization, this role leverages advanced machine learning tools and data mining techniques to identify and combat fraud. A key focus of the role is on data and feature engineering; transforming raw and complex datasets into optimized inputs for developing high-performance fraud models. The role will be responsible for developing and implementing sophisticated fraud models aimed at preventing and mitigating fraud risks across the full fraud lifecycle including application fraud, synthetic ID fraud, account takeover, and evolving fraud attack methods. The ideal candidate will bring a strong technical background in data processing, feature engineering, and data manipulation, playing a pivotal role in enabling the development of effective and scalable fraud models. The role requires expertise in extracting and engineering key features from large datasets, ensuring that models are not only accurate but also resilient against emerging fraud patterns. The role will work closely with technology teams, fraud analytics, and various business partners to stay informed about business and technology shifts, identifying both potential and existing fraud impacts. Technical proficiency in model optimization, algorithm development, and real-time analytics is essential for enhancing fraud prevention efforts.

Responsibilities

• Lead data and feature engineering efforts to extract, transform, and prepare high-quality data inputs for fraud model development, focusing on identifying key attributes that drive accurate fraud detection.
• Build predictive models and machine-learning and AI algorithms with large amounts of structured and unstructured data.
• Ownership and management of fraud models, risk appetite execution and defect analysis.
• Design, develop, and implement advanced machine learning models to detect and prevent fraud across the entire lifecycle, including application fraud, synthetic ID fraud, account takeover, and evolving attack schemes.
• Utilize advanced data processing techniques to manage large, complex datasets, including data cleaning, normalization, and augmentation, ensuring robust model performance.
• Conduct comprehensive exploratory data analysis (EDA) to uncover hidden patterns, trends, and anomalies that can inform model development and feature engineering.
• Collaborate closely with technology teams, fraud analytics, and business partners to align on data strategies, stay updated on industry trends, and proactively identify potential and existing fraud risks.
• Continuously optimize and refine fraud models through feature selection, hyperparameter tuning, and ongoing performance monitoring, ensuring models remain adaptive to new fraud tactics.
• Support model deployment and integration into production systems, ensuring seamless real-time fraud detection and efficient feedback loops for continuous model improvement.
• Evaluate and select appropriate machine learning algorithms and tools based on specific fraud detection needs and data characteristics.
• Engage in cross-functional initiatives to enhance data quality and governance, improving overall fraud prevention capabilities.
• Participate in model validation and testing processes to ensure compliance with regulatory standards and alignment with best practices in fraud risk management.
• Generate and manage regular and ad-hoc reporting to enable effective monitoring and identification of emerging trends.

Requirements

• Bachelor’s Degree required in statistics, mathematics, physics, economics, or other analytical or quantitative discipline.
• Master's Degree or PhD preferred.
• 5+ years in data science, machine learning, or advanced analytics.
• Experience with Generative AI and LLM, preferred.
• Proficiency in programming languages such as Python, R, or SQL for data manipulation, feature engineering, and model development.
• Strong experience with data processing tools and libraries (e.g., Pandas, Numpy, PySpark) for handling large and complex datasets.
• Deep understanding of machine learning algorithms (e.g., decision trees, gradient boosting, neural networks, natural language processing) and statistical modeling techniques used for fraud detection.
• Expertise in feature engineering, including creating, selecting, and refining features to improve model accuracy and performance.
• Experience with building and optimizing data pipelines, ETL processes, and real-time data streaming for fraud detection solutions.
• Familiarity with model development, monitoring, and versioning in production environments.
• Strong ability to conduct exploratory data analysis (EDA) and identify actionable insights from large datasets to drive model development.
• Proven track record of working cross-functionally with technology, analytics, and business teams to implement and optimize fraud prevention strategies.
• Ability to translate complex technical findings into clear, actionable insights for non-technical stakeholders and business leaders.
• Strong problem-solving skills with the ability to think critically and creatively in a fast-paced environment.
• Familiarity with regulatory requirements and best practices related to fraud modeling and risk management.
• Demonstrated ability to manage multiple projects and priorities simultaneously while meeting tight deadlines.
• High level of attention to detail and precision in data analysis, model development, and reporting.
• Strong intellectual curiosity and eagerness to stay updated with the latest developments in data science, machine learning, and fraud detection techniques.

Benefits

• medical, dental & vision coverage
• 401(k)
• life, accident, and disability insurance
• wellness programs
• paid time off packages, including planned time off (vacation), unplanned time off (sick leave), and paid holidays