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Research & field notes

What we have learned collecting AI training data

20 practical write-ups on how much data a model actually needs, what a training licence has to say, why low-resource languages fail, and how collection is really done. No gated PDFs, no lead-capture walls.

Practical guides

Practical guides

How much audio do you need to fine-tune an ASR model?

How many hours of speech data you actually need to fine-tune an ASR model, with realistic thresholds for 200, 500, 2,000 and 10,000 hours.…

8 min read ·

Free datasets vs commissioned collection: when to pay

Common Voice, FLEURS and OpenSLR are free and often sufficient. Here is exactly when open data runs out and commissioned collection becomes …

8 min read ·

Quota sampling beats volume: how to specify a dataset

Why 500 well-distributed hours beat 5,000 convenience-sampled ones, which axes to quota on, and how to write a data specification that survi…

7 min read ·

How much data does a TTS voice need?

How many studio hours a text-to-speech voice actually needs, why TTS data differs completely from ASR data, and what phonetic balance means …

7 min read ·

What makes SFT data good, and why translated data is not

What separates useful instruction fine-tuning data from filler, how many pairs you need, and why translating an English seed set produces a …

8 min read ·

How to choose an AI training data vendor: 12 questions

Twelve questions that separate serious data vendors from resellers: provenance, consent, QA methodology, pay transparency and what happens w…

8 min read ·

How to run a speech data collection project

End to end: writing the spec, recruiting to quota, choosing capture conditions, transcription standards, QA gates and acceptance testing.…

9 min read ·

How to actually measure data annotation quality

Gold seeding, double-blind passes and senior adjudication — the three layers that produce trustworthy labels, and what a delivery report mus…

8 min read ·

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