Out of Sample
about

Out of Sample

A course in applied neural networks.

The figures here move: push them. Every setting you reach is kept in the address, so a link carries it.

Select any passage to write beside it, in the left margin.

Turn with the arrow keys, the space bar, a swipe, or the arrows at the top right.
Part I, Optimisation, generalisation, adaptationWinter 2027

Part I

  1. Downhill

    Training a network is walking down a surface you cannot see, one gradient at a time. How big a step you take matters more than almost anything else.

  2. The part you didn’t fit

    A model judged on the data it learned from will always flatter itself. Hide some of the data, and the flattery stops.

  3. A small change to a large matrix

    Fine-tuning a pretrained model rarely needs to move every weight. LoRA trains a low-rank correction instead, and loses surprisingly little.

  4. What survives the bottleneck

    An autoencoder learns by copying its input through a code. Make the code narrow, make it a distribution, or make it sparse, and you get three different models that answer three different questions.

Part II, Sparse autoencoders