Stephen M.

Key Skills

Software

No software listed

Top Subject Matter

AI training data for preference/prompt-response evaluation and safety quality assurance

Client CV/NLP dataset annotation and RLHF preference data creation

Top Data Types

Text

Image

Top Task Types

Entity (NER) Classification

RLHF

Red Teaming

Freelancer Overview

AI Trainer / Data Annotation Specialist. Brings 6+ years of professional experience across complex professional workflows, research, and quality-focused execution. Core strengths include Internal and Proprietary Tooling. Education includes Master of Science, University of Nairobi (2021) and Bachelor of Science, University of Nairobi (2019). AI-training focus includes data types such as Text and labeling workflows including Evaluation, Rating, and Named Entity Recognition.

Labeling Experience

AI Trainer / Data Annotation Specialist, MindSpec (Jan 2023 - May 2026)

TextEntity (NER) Classification

Led AI training and annotation quality improvements by calibrating annotators and monitoring label accuracy. Translated model failure modes into targeted data collection and re-labeling strategies with ML engineers. Conducted manual red teaming and adversarial prompt testing to flag harmful, biased, or low-quality outputs prior to deployment. • Calibration sessions for a team of 8 junior annotators • Improved average label accuracy from 87% to 96% • Re-labeling strategies based on model failure modes • Red teaming and adversarial prompt testing

2023 - 2026

Data Annotation Associate, BlackSky (Jun 2021 - Dec 2022)

TextRLHFRed Teaming

Annotated and validated text, image, and audio datasets for CV and NLP client projects. Worked on pilot RLHF tasks by ranking chatbot responses for helpfulness, harmlessness, and factual accuracy. Reported systemic labeling tool issues and supported team workflow improvements. • Text dataset tagging and validation • Multi-modal annotation involvement (text, image, audio) • RLHF chatbot response ranking (helpfulness/harmlessness/factuality) • Identified tool issues and contributed to workflow improvements

2021 - 2022

Education

Work History