Samuel N.

Key Skills

Software

Appen

Other

Top Subject Matter

NLP/ASR transcription

speaker diarization

and subtitle generation (multilingual Kenyan English/Kiswahili)

Top Data Types

Audio

Video

Text

Document

Top Task Types

Transcription

Entity (NER) Classification

Freelancer Overview

Audio/Video Data Annotation & Transcription Specialist (NLP/ASR). Brings 5+ years of professional experience across complex professional workflows, research, and quality-focused execution. Core strengths include Appen and Other. Education includes Bachelor of Arts, University of Nairobi (2022) and Kenya Certificate of Secondary Education, Lenana School (2018). AI-training focus includes data types such as Audio and labeling workflows including Transcription, Named Entity Recognition, and Evaluation.

Labeling Experience

Language Curriculum & Assessment Developer

OtherAudio

Designed and moderated multilingual English and Kiswahili examination items using evidence-based validity and reliability frameworks to raise assessment reliability. Delivered training on standardized rubrics for nationwide teachers, reducing inter-rater scoring variance across pilot cohorts. Authored multilingual instructional content across Kikuyu, English, and Kiswahili curriculum units with linguistic precision tailored to different language registers. • Built and moderated 300+ multilingual assessment items • Trained 120+ teachers on rubric application • Reduced inter-rater scoring variance by 18% in pilot cohorts • Authored content for 15+ curriculum units across three language registers

2022 - Present

Multilingual Performance & Localization Practitioner

OtherAudio

Applied native-level register calibration across Kenyan English, Kiswahili, and Kikuyu to support culturally localized live productions. Co-created bilingual study guides and delivered performances in three native languages, demonstrating cross-linguistic accuracy relevant to high-quality ASR data annotation practices. Translated localization and register-tuning experience into accent precision and code-switching fluency for multilingual language work. • Calibrated registers across 120+ live productions • Co-created bilingual study guides used across 120+ schools • Delivered culturally localized performances in three native languages • Supported accent precision and code-switching fluency for multilingual outputs

2021 - 2023

Audio/Video Data Annotation & Transcription Specialist (NLP/ASR)

AppenAudioTranscriptionEntity (NER) Classification

Provided speaker-diarized, time-coded ASR training transcripts for Kenyan English and Kiswahili audio, applying rigorous self-QA using WER/CER metrics before each submission batch. Produced bilingual subtitle files (SRT/VTT/SDH) while ensuring zero PII violations and creating/using labeling guidelines for contributors. Captured code-switching patterns across four native languages to improve model training quality and reduce common ASR misclassifications. • Sustained 98%+ transcription accuracy across 500+ hours of multilingual audio • Time-coded, speaker-diarized transcripts for ASR model training • Subtitle generation in SRT, VTT, and SDH formats for 200+ assets • Compliance-focused labeling including PII checks and guideline authoring

2021 - 2023

Education

Work History