Stephen Njihia

Key Skills

Software

Label Studio

Top Subject Matter

No subject matter listed

Top Data Types

Text

Top Label Types

Entity Ner Classification

Freelancer Overview

I am an experienced AI Data Collection Specialist with over five years supporting machine learning and computer vision projects for global clients. My expertise spans structured video and image data collection, annotation, metadata tagging, and rigorous quality assurance for large-scale training datasets, especially in fraud detection, identity verification, and risk analysis. I am highly skilled in using tools like Appen Mobile, CrowdGen, Excel, and Google Sheets to deliver high-integrity, audit-ready datasets that improve AI model accuracy and reliability. My background includes hands-on work with image labeling, bounding boxes, and dataset auditing, as well as collaborating with cross-functional teams to meet strict project specifications and compliance standards. I am committed to ethical AI development and data privacy, consistently maintaining a 100% acceptance rate and delivering high-quality results for clients on platforms such as Upwork and Fiverr.

Labeling Experience

CHAT&TEXT DATA ANNOTATION FOR AI MODERATION

Label StudioTextEntity Ner Classification

Worked on text and chat data annotation projects focused on improving AI moderation and conversational accuracy. Tasks included classifying messages by intent and sentiment, identifying harmful or inappropriate content, tagging named entities, and labeling emotional tone. Maintained high accuracy by strictly following annotation guidelines, performing regular quality checks, and meeting tight deadlines while handling large datasets

Worked on text and chat data annotation projects focused on improving AI moderation and conversational accuracy. Tasks included classifying messages by intent and sentiment, identifying harmful or inappropriate content, tagging named entities, and labeling emotional tone. Maintained high accuracy by strictly following annotation guidelines, performing regular quality checks, and meeting tight deadlines while handling large datasets

2023 - 2025

Education

Work History