But we had a classic chicken-and-egg problem—we needed data to train the model, but we didn't have any real examples yet. So we started by having Claude generate about 50 synthetic examples that we added to our dataset. We then used that initial fine-tune to ship an early version of Zeta behind a feature flag and started collecting examples from our own team's usage.
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This approach let us quickly build up a solid dataset of around 400 high-quality examples, which improved the model a lot!
I checked the training set, but couldn't quickly identify which were 'Claude' produced[2]. Would be interesting to see them distinguished out.
Francis Bach, the author, makes a good faith effort to explain exactly why this material is beneficial (see https://francisbach.com/my-book-is-out/):
"Why yet another book on learning theory? ...the main reason is that I felt that the current trend in the mathematical analysis of machine learning was leading to overly complicated arguments and results that are often not relevant to practitioners. Therefore, my aim was to propose the simplest formulations that can be derived from first principles, trying to remain rigorous without overwhelming readers with more powerful results that require too much mathematical sophistication."
From my own reading and experience on the mathematical analysis approach of this "training goes brrr" approach, I thought the material in Chapter 12, Overparameterized Models, was interesting and coherent with 12.2.4 Linear Regression with Gaussian Projections being an especially elegant explanation. It would be interesting to hear if you had read/skimmed/purused this section and found it wanting etc.