As (maybe) mentioned in the slides, this method may not be computationally feasible for SOTA models, but I’m interested in the ordering of features turned monosemantic; if the most important features are turned monosemantic first, then you might not need full monosemanticity.
I initially expect the “most important & frequent” features to become monosemantic first based off the superposition paper. AFAIK, this method only captures the most frequent because “importance” would be w/ respect to CE-loss in the model output, not captured in reconstruction/L1 loss.
In fact, we might be able to speed up the learning of common features even further:
Pierre Peigné at SERIMATS has done some interesting work that looks at initialization schemes that speed up learning. If you initialize the autoencoders with a sample of datapoints (e.g. initialize the weights with a sample from the MLP activations dataset), each of which we assume to contain a linear combination of only a few of the ground truth features, then the initial phases of feature recovery is much faster*. We haven’t had time to check, but it’s presumably biased to recover the most common features first since they’re the most likely to be in a given data point.
*The ground truth feature recovery metric (MMCS) starts higher at the beginning of autoencoder training, but converges to full recovery at about the same time.
As (maybe) mentioned in the slides, this method may not be computationally feasible for SOTA models, but I’m interested in the ordering of features turned monosemantic; if the most important features are turned monosemantic first, then you might not need full monosemanticity.
I initially expect the “most important & frequent” features to become monosemantic first based off the superposition paper. AFAIK, this method only captures the most frequent because “importance” would be w/ respect to CE-loss in the model output, not captured in reconstruction/L1 loss.
I strongly suspect this is the case too!
In fact, we might be able to speed up the learning of common features even further:
Pierre Peigné at SERIMATS has done some interesting work that looks at initialization schemes that speed up learning. If you initialize the autoencoders with a sample of datapoints (e.g. initialize the weights with a sample from the MLP activations dataset), each of which we assume to contain a linear combination of only a few of the ground truth features, then the initial phases of feature recovery is much faster*. We haven’t had time to check, but it’s presumably biased to recover the most common features first since they’re the most likely to be in a given data point.
*The ground truth feature recovery metric (MMCS) starts higher at the beginning of autoencoder training, but converges to full recovery at about the same time.