Robert K.

Key Skills

Software

Appen

Mindrift

Toloka

Other

Top Subject Matter

LLM training data

RLHF preference labeling

AI safety and alignment

Top Data Types

Text

Image

Document

Top Task Types

RLHF

Classification

Diagnosis

Freelancer Overview

Senior Data Labeler / AI Training Data Specialist (xAI Solutions). Brings 8+ years of professional experience across legal operations, contract review, compliance, and structured analysis. Core strengths include Internal and Proprietary Tooling. Education includes Master of Science, University of Nairobi (2020) and Bachelor of Science, Strathmore University (2018). AI-training focus includes data types such as Text and Image and labeling workflows including RLHF, Classification, and Diagnosis.

Labeling Experience

Senior Data Labeler / AI Training Data Specialist (xAI Solutions)

TextRLHF

Led a team to label high-quality instruction-response pairs for fine-tuning large language models and improved inter-annotator agreement to 96.8%. Created detailed annotation guidelines and rubrics for RLHF preference data to enhance model alignment and reduce toxic outputs. Conducted quality audits on large sample volumes and performed red-teaming by labeling adversarial prompts and harmful content for AI safety guardrails. • Labeled 450,000+ instruction-response pairs for fine-tuning. • Developed RLHF preference labeling guidelines and rubrics. • Audited 150,000+ samples to correct systematic labeling errors. • Labeled adversarial/harmful prompts for multilingual AI safety training.

2023 - Present

AI Data Annotation Lead (Safaricom AI Lab)

ImageClassification

Managed end-to-end labeling for computer vision and NLP datasets used in fraud detection and customer service AI systems. Developed and enforced annotation standards to improve production model performance metrics. Labeled large volumes of images and text and worked with ML engineers using model error analysis to iteratively refine datasets. • Annotated 280,000+ images for computer vision use cases. • Labeled 120,000 text samples for NLP applications. • Trained and mentored 18 junior labelers on metrics and labeling best practices. • Performed sentiment analysis, intent classification, and entity recognition labeling with high accuracy.

2021 - 2023

Data Annotation Specialist (University of Nairobi – AI Research Center)

ImageDiagnosis

Annotated agricultural image datasets for computer vision models used by smallholder farmers. Labeled low-resource language text datasets for NLP research including machine translation and speech recognition. Contributed to bias detection and ethical labeling initiatives and maintained thorough documentation and versioning for labeled datasets. • Labeled agricultural crop disease and pest identification images. • Labeled 85,000+ low-resource text samples for Kiswahili NLP projects. • Supported bias detection and ethical labeling for balanced demographic representation. • Maintained dataset documentation and version control for research datasets.

2019 - 2021

Education

Work History