Open to opportunities

James Marcos

@jamesmarcos

Message

Senior Data Specialist focused on AI data quality, RLHF, and scalable annotation workflows.

United States

Message

What I'm looking for

I seek roles where I can lead AI data quality, improve RLHF/model safety, mentor teams, and scale annotation workflows in ethical, impact-driven environments.

I am a Senior Data Specialist with 7 years of experience leading AI content, data annotation, and training programs for Tier-1 LLM and autonomous vehicle projects. I specialize in RLHF, LiDAR, NLP, and segmentation, and have reduced labeling error rates and improved review efficiency through calibrated golden sets and robust training modules.

I hold a B.S. in Data Science & Communication and certifications including Labelbox Certified Data Strategist and Certified Ethical Emerging Technologist. I am committed to model safety, bias mitigation, and pragmatic deployment—leveraging SQL, Python, Labelbox, and Scale AI to deliver higher data accuracy and reliable model performance.

Experience

Work history, roles, and key accomplishments

Current

Lead AI Content & Training Specialist

Current

Scale AI

Jan 2021 - Present (5 years 2 months)

Evaluated and ranked 10,000+ LLM responses for reasoning and safety, developed Golden Sets that reduced manual review time by 20%, and mentored a team of 10 junior annotators.

Prompt Engineering Model Evaluation Labelbox Data Annotation Mentoring

Data Quality Analyst

Appen

Feb 2017 - Dec 2020 (3 years 10 months)

Managed end-to-end data pipelines for autonomous vehicle projects and reduced labeling error rates from 8% to 0.5% while authoring 30+ technical training modules for global teams.

Data Annotation LiDAR Segmentation SQL Python Training Development Quality Assurance Labeling Pipelines

Education

Degrees, certifications, and relevant coursework

Stanford University (via DeepLearning.AI)

Certificate, Machine Learning / RLHF

2024 - 2024

Completed an online specialization in reinforcement learning from human feedback, model alignment, and prompt engineering.

CertNexus

Certificate, AI Ethics / Data Privacy

2023 - 2023

Completed the Certified Ethical Emerging Technologist program specializing in AI ethics, data privacy (GDPR/CCPA), and bias mitigation.

Labelbox Academy

Certificate, Data Annotation / Labeling Platforms

2022 - 2022

Obtained an expert-level certification in advanced Labelbox workflows for image segmentation, video annotation, and text-based RLHF pipelines.

University of California, Berkeley

Bachelor of Science, Data Science & Communication

2013 - 2017

Completed a Bachelor of Science focused on data ethics, machine learning, and linguistic analysis with a senior project on automating sentiment analysis in large datasets.