Logan Riggs Smith

Logan's been working in mech interp since 2023, co-authoring the first SAE paper. His main focus is on resolving our underlying confusions about model internals. This comes from a belief that ambitious mech interp is a verifiable task ("does the algorithm extracted match the model?"), but we need to properly define "simplicity", "features", and "circuits" first.

Projects

Research Direction: Ambitious Mech Interp w/ Tensor-transformers on Toy Languages

Many toy models don't generalize to LLMs. To handle this, we can create an increasingly realistic toy language, starting with known primitives (induction heads, skip-trigrams) in order to resolve our fundamental confusions. There are many ways to contribute:

1. Interp-across-time: are there any dependent structures during training (eg must learn X before learning Y)?
2. Building interp tools: What techniques (existing or novel) can be used to find these ground truth features?
3. Phenomenon Studies: use the controlled setup to characterize specific computational phenomena (suppression, error correction, compositional reuse) with ground-truth verification.
4. Tensor Interp: because we're using a tensor-transformer, there may be new techniques available to us (prior familiarity with tensor networks is a prerequisite for this direction)
5. Improve the data-generating process (DGP): Extend the DGP to include computational patterns beyond n-grams & induction (eg nested structure (brackets, quotes), long-range dependencies, context-sensitive transitions, etc) learned from existing datasets.

Full Project Link: https://docs.google.com/document/d/1x5Ahn7-XSeln5lKWw2C9aORnDASzLlRzjVPiTLi60jM/edit?usp=sharing

What we’re looking for in a Mentee

We're looking for someone who's smart and gets work done. Some independence to pursue your own experiments & hypotheses is expected. To clarify, we'll give quick feedback but will not fully scope out the entire project for you.

You do NOT need a background in tensor networks.

What we’re like as Mentors

We typically have ~1 hour weekly meetings, giving feedback on the experiments tried and ideas on what to try next. As needed, we also have 1-on-1 meetings for brainstorming ideas and to get mentees unstuck. Will respond within a day or two to any updates.