Julius Felix Valentin Köller

Key Skills

Software

Other

OneForma

Top Subject Matter

Large Language Models (LLMs)

Linguistics Domain Expertise

AI Training

Top Data Types

Text

Audio

Video

Top Task Types

Text Summarization

Transcription

Prompt Response Writing SFT

Data Collection

Classification

Question Answering

Evaluation Rating

Point Key Point

Freelancer Overview

Freelance AI Training Specialist & Linguistic Evaluator. Brings 3+ years of professional experience across complex professional workflows, research, and quality-focused execution. Core strengths include OneForma. AI-training focus includes data types such as Text and labeling workflows including Translation and Localization.

Labeling Experience

Freelance AI Training Specialist & Linguistic Evaluator

OneformaText

As a freelance AI Training Specialist & Linguistic Evaluator, I contributed to the optimization and fine-tuning of Large Language Models (LLMs) for top AI firms. My work included high-stakes linguistic evaluation, expert English-to-German translations, adversarial testing, and quality assurance of AI-generated content. I ensured high-fidelity training data by managing multimodal projects involving technical annotation and audio-to-text localization. • Specialization in RLHF, ranking, evaluation, and refinement of AI responses. • Conducted adversarial testing and quality assurance, identifying model hallucinations. • Managed transcription and localization of audio/text datasets for LLMs. • Ensured linguistic, grammatical, and cultural accuracy across training workflows.

As a freelance AI Training Specialist & Linguistic Evaluator, I contributed to the optimization and fine-tuning of Large Language Models (LLMs) for top AI firms. My work included high-stakes linguistic evaluation, expert English-to-German translations, adversarial testing, and quality assurance of AI-generated content. I ensured high-fidelity training data by managing multimodal projects involving technical annotation and audio-to-text localization. • Specialization in RLHF, ranking, evaluation, and refinement of AI responses. • Conducted adversarial testing and quality assurance, identifying model hallucinations. • Managed transcription and localization of audio/text datasets for LLMs. • Ensured linguistic, grammatical, and cultural accuracy across training workflows.

2020 - Present

Freelance Language Consultant & Translator (AI Text Evaluation)

OtherTextTranscription

Reviewed and audited AI-generated and machine-translated text for linguistic naturalness and grammatical accuracy. Tasks included correcting robotic phrasing, verifying the appropriate use of German register, and ensuring localized content met high cultural and syntactic standards. Coordinated workflow between international stakeholders to deliver consistent and reliable language AI evaluations. • Focused on enhancing quality of AI-generated text output for technical and corporate content • Performed evaluation for text naturalness, relevance, and formal/informal register • Ensured high data integrity and accuracy throughout multilingual projects • Delivered feedback and improvements for AI/ML model performance

Reviewed and audited AI-generated and machine-translated text for linguistic naturalness and grammatical accuracy. Tasks included correcting robotic phrasing, verifying the appropriate use of German register, and ensuring localized content met high cultural and syntactic standards. Coordinated workflow between international stakeholders to deliver consistent and reliable language AI evaluations. • Focused on enhancing quality of AI-generated text output for technical and corporate content • Performed evaluation for text naturalness, relevance, and formal/informal register • Ensured high data integrity and accuracy throughout multilingual projects • Delivered feedback and improvements for AI/ML model performance

2016 - 2026

Education

Work History