Kierra Barnwell

Key Skills

Software

Appen

Labelbox

CVAT

Scale AI

Top Subject Matter

Natural Language Processing

Computer Vision

Autonomous Vehicles/Robotics

Top Data Types

Text

Image

Video

Audio

Top Task Types

Entity Ner Classification

Bounding Box

Point Key Point

Transcription

Polygon

Freelancer Overview

Senior Data Annotation Specialist. Brings 8+ years of professional experience across complex professional workflows, research, and quality-focused execution. Core strengths include Appen, Labelbox, and CVAT. Education includes Master of Science, University of Nairobi (2019) and Bachelor of Science, University of Nairobi (2017). AI-training focus includes data types such as Text, Image, and Video and labeling workflows including Entity (NER) Classification, Bounding Box, and Key Point.

Labeling Experience

Senior Data Annotation Specialist

CVATVideoPoint Key Point

As part of my responsibilities at DataForce, I annotated video datasets with keypoint marking for tracking and robotics applications. My work included semantic segmentation and consistent annotation review to reduce error rates by 30%. I managed edge-case escalation and took part in mentoring efforts for junior video annotators. • Annotated keypoints and performed video segmentation • Implemented object tracking and motion labeling • Conducted QA audits on complex sequences • Escalated ambiguities or difficult cases for project improvement

As part of my responsibilities at DataForce, I annotated video datasets with keypoint marking for tracking and robotics applications. My work included semantic segmentation and consistent annotation review to reduce error rates by 30%. I managed edge-case escalation and took part in mentoring efforts for junior video annotators. • Annotated keypoints and performed video segmentation • Implemented object tracking and motion labeling • Conducted QA audits on complex sequences • Escalated ambiguities or difficult cases for project improvement

2022 - Present

Senior Data Annotation Specialist

LabelboxImageBounding Box

I annotated image datasets for computer vision projects, using bounding boxes and semantic segmentation techniques. My role contributed to autonomous vehicle and robotics training pipelines, focusing on precision and quality. I mentored team members on image annotation protocols and resolved edge cases in image classification. • Draw bounding boxes and perform segmentation for vehicle perception • Keypoint marking for robotics vision tasks • Review annotated data for inconsistencies • Achieved consistently high accuracy in image labeling

I annotated image datasets for computer vision projects, using bounding boxes and semantic segmentation techniques. My role contributed to autonomous vehicle and robotics training pipelines, focusing on precision and quality. I mentored team members on image annotation protocols and resolved edge cases in image classification. • Draw bounding boxes and perform segmentation for vehicle perception • Keypoint marking for robotics vision tasks • Review annotated data for inconsistencies • Achieved consistently high accuracy in image labeling

2022 - Present

Senior Data Annotation Specialist

AppenTextEntity Ner Classification

As a Senior Data Annotation Specialist at DataForce by TransPerfect, I led annotation of large-scale NLP datasets involving sentiment analysis, entity extraction, and coreference resolution. My work focused on producing consistent and high-quality labels for Fortune 500 AI clients, ensuring ground-truth accuracy. I was responsible for reviewing, auditing, and mentoring within NLP labeling workflows. • Led annotation and QA of sentiment and entity recognition tasks on large corpora • Maintained inter-annotator agreement scores above 95% • Mentored junior annotators on best practices and guidelines • Conducted RLHF evaluation to align language models with human feedback

As a Senior Data Annotation Specialist at DataForce by TransPerfect, I led annotation of large-scale NLP datasets involving sentiment analysis, entity extraction, and coreference resolution. My work focused on producing consistent and high-quality labels for Fortune 500 AI clients, ensuring ground-truth accuracy. I was responsible for reviewing, auditing, and mentoring within NLP labeling workflows. • Led annotation and QA of sentiment and entity recognition tasks on large corpora • Maintained inter-annotator agreement scores above 95% • Mentored junior annotators on best practices and guidelines • Conducted RLHF evaluation to align language models with human feedback

2022 - Present

Data Labeling Analyst

AppenAudioTranscription

While working at Appen, I transcribed and labeled audio datasets with a focus on speaker identification and emotion tagging for speech AI systems. My tasks addressed accuracy, ambiguity resolution, and robust annotation for training automatic speech recognition models. I consistently received top accuracy ratings and contributed to annotation guideline development. • Transcribed audio and labeled speech features • Performed speaker diarization and emotion tagging • Collaborated to resolve ambiguous scenarios • Supported deployment of ASR and voice AI models

While working at Appen, I transcribed and labeled audio datasets with a focus on speaker identification and emotion tagging for speech AI systems. My tasks addressed accuracy, ambiguity resolution, and robust annotation for training automatic speech recognition models. I consistently received top accuracy ratings and contributed to annotation guideline development. • Transcribed audio and labeled speech features • Performed speaker diarization and emotion tagging • Collaborated to resolve ambiguous scenarios • Supported deployment of ASR and voice AI models

2020 - 2021

Data Labeling Analyst

AppenTextEntity Ner Classification

At Appen, I performed high-volume text annotation including named entity recognition, part-of-speech tagging, and relation extraction for NLP model training. My efforts contributed directly to the development of high-accuracy language models for major clients. I ensured task quality by following strict guidelines and addressing ambiguous cases. • Labeled and classified entities and relationships in text • Applied part-of-speech tagging protocols • Collaborated on guideline and QA process improvements • Achieved 98%+ accuracy in task performance

At Appen, I performed high-volume text annotation including named entity recognition, part-of-speech tagging, and relation extraction for NLP model training. My efforts contributed directly to the development of high-accuracy language models for major clients. I ensured task quality by following strict guidelines and addressing ambiguous cases. • Labeled and classified entities and relationships in text • Applied part-of-speech tagging protocols • Collaborated on guideline and QA process improvements • Achieved 98%+ accuracy in task performance

2020 - 2021

Show more

Education

Work History