logoalt Hacker News

NitpickLawyer • today at 7:20 PM • 3 replies • view on HN

> As a result, Astra spots and fixes a common failure of tiny reasoning models: they loop [13]. When the base model loops, it repeats the same text and rarely reaches an answer (85 of its first 96 practice answers ran to the 32,768-token limit). Astra traced the looping to one direction written by the MLPs of layers 15 and 19, and subtracted that direction from 64 output columns in each (131,072 weights), much like removing a behavior by deleting a single direction from a model’s weights

HA! Now that's cool. Not necessarily the improvements, those are ancient and probably overtrained benchmarks, but it's so cool that the model found a singular direction for this "loop bug". I imagine it could possibly do much the same thing in finding other "single directions" on a variety of topics (if allowed by guardrails). This is really really cool, especially for the mechinterp folks.


Replies

prophesi • today at 8:09 PM

It's pretty much how abliteration works too; find where the refusals are happening and flip the bit.

tty456 • today at 9:17 PM

Like altering DNA

ctkhn • today at 8:33 PM

Can't wait to see qwen4 and qwen5 as this becomes more common.