Alexander B.

Key Skills

Software

Remotasks

Appen

Other

Top Subject Matter

LLM / RLHF response evaluation and quality rating

Computer vision datasets for autonomous vehicle perception and object detection

Multilingual audio transcription and ASR training annotations

Top Data Types

Text

Image

Audio

Top Task Types

Bounding Box

Transcription

Entity (NER) Classification

Fine-tuning

Freelancer Overview

AI Data Specialist & Annotation Expert (Freelance) — RLHF and LLM Response Evaluation. Brings 2+ years of professional experience across complex professional workflows, research, and quality-focused execution. Core strengths include Remotasks, Appen, and Other. Education includes Bachelor of Science, University of Nigeria, Nsukka (2023). AI-training focus includes data types such as Text, Image, and Audio and labeling workflows including Evaluation, Rating, and Bounding Box.

Labeling Experience

AI Data Specialist & Annotation Expert (Freelance) — Multilingual audio transcription

OtherAudioTranscription

Transcribed and annotated multilingual audio for ASR model training and evaluation. Labeled speaker changes, background noise, emotion, and audio clarity to improve model robustness and quality. Achieved high tagging accuracy during delivery. • Transcribed and annotated 150+ hours of multilingual audio (English, Igbo, Pidgin) • Tagged speaker changes, background noise, emotion, and audio clarity • 97%+ accuracy on tagged audio attributes • Supported ASR model training pipelines via structured audio annotations

2023 - Present

AI Data Specialist & Annotation Expert (Freelance) — Image annotation for object detection/segmentation

AppenImageBounding Box

Created vision annotations for object detection and perception training data, including bounding boxes, segmentation masks, and attribute tags. Applied labeling for real-world categories used in autonomous vehicle contexts such as vehicles, pedestrians, traffic signs, and road markings. Completed large-scale batches with high quality and reliable delivery. • Labeled 25,000+ images with bounding boxes, segmentation masks, and attribute tags • Maintained zero QA rejections on final delivery • Produced 98.5% quality score across autonomous vehicle annotation batches • Categorized objects by type, position, and occlusion level

2023 - Present

AI Data Specialist & Annotation Expert (Freelance) — RLHF and LLM Response Evaluation

RemotasksText

Performed pairwise comparison evaluations for RLHF pipelines, rating AI-generated response pairs on factual accuracy, helpfulness, safety, and stylistic quality. Supported LLM fine-tuning by identifying model failure patterns and providing structured quality rationales. Ensured consistent rating quality across evaluation batches. • Rated 900+ response pairs monthly • Evaluated 3,500+ AI-generated text responses for factuality, relevance, helpfulness, safety, and tone • Zero rework requests from QA reviewers in evaluated batches • Escalated 140+ model failure patterns to client ML teams for targeted improvement

2023 - Present

Freelance AI Data Consultant & Web Developer — NLP data labeling

OtherTextEntity (NER) Classification

Created and labeled custom NLP datasets for intent classification, named entity recognition (NER), and sentiment analysis for AI startup clients. Built annotation schemas and wrote detailed labeling guidelines to improve consistency and reduce inter-annotator disagreement. Enabled client validation success by aligning annotations to evaluation benchmarks. • Curated and labeled NLP training datasets for 8 AI startup clients • Achieved average 93% model accuracy on client validation benchmarks • Reduced inter-annotator disagreement by 38% for a content moderation startup • Produced intent classification, NER (entities), and sentiment analysis training labels

2022 - 2024

Education

Work History