Kien N.

Key Skills

Software

Other

CVAT

Top Subject Matter

Machine learning and data/content quality evaluation

Data annotation/annotation pipeline modeling and data quality preparation

Legal Services & Contract Review

Top Data Types

Text

Document

Image

Video

Top Task Types

Function Calling

Classification

Data Collection

Freelancer Overview

Exploratory Tester (data labeling & classification for ML training). Core strengths include CVAT, DataAnnotation.tech, and RWS. Education includes Master of Science, Hanoi University of Science and Technology (HUST). AI-training focus includes data types such as Text, Image, and Video and labeling workflows including Classification and Data Collection.

Labeling Experience

Data Annotator at Invisible Technology

OtherTextFunction CallingData Collection

Worked as a data annotator to create data models and document data flows intended to improve system architecture and data quality. Built a data warehouse integrating data from multiple sources to enable reliable downstream use. Developed an enterprise data model that supported consistent data access across the organization. • Created data models and documented data flows • Improved data quality and system architecture • Integrated data from multiple sources into a data warehouse • Built an enterprise data model for consistent data access

2025 - Present

Exploratory Tester (data labeling & classification for ML training)

CVATTextClassification

Performed high-quality data labeling and classification across diverse datasets to support machine learning model training. Collaborated with AI engineers and project managers to align on annotation guidelines and ensure consistent interpretation. Identified edge cases and inconsistent data within large datasets to maintain high model accuracy and reliability. • Labeled text, image, and video data for training • Participated in validation and auditing cycles for labeled-set integrity • Flagged problematic samples and supported reliability improvements • Ensured adherence to data privacy and security protocols

2023 - 2025

Quality Rater at Oneforma (Quality evaluation and rating)

OtherText

Served as a quality rater by evaluating content and AI-related outputs against established guidelines to ensure accuracy, relevance, and compliance with quality standards. Applied detailed rating criteria to assess performance, identify deficiencies, and flag potential risks or policy violations. Produced consistent, well-documented evaluations while maintaining productivity and accuracy under tight turnaround timelines. • Evaluated content/outputs per rubric • Identified deficiencies and risk/policy issues • Delivered objective, well-documented feedback • Collaborated with QA teams for process and product improvement

2023 - 2025

Education

Work History