I started from Memphis-CoT 3B, which used a novel iterative contrastive finetuning procedure to improve reasoning ability.
I first generated completions just as in each of the Memphis-CoT cycles.
Then, for each example in the dataset, I sampled a correct and incorrect completion. I applied the same ranking loss over these completions (with a weight of 0.2), but applied the cross-entropy loss over the example tokens instead of the completion tokens.
Finally, I averaged it with the Memphis-CoT model prior to the additional training, again with spherical linear interpolation, this time with a weight of 0.8.
This model performs significantly worse than Memphis-CoT on benchmarks, despite being better suited to chat and creative writing tasks. This is an expected tradeoff, especially for small models.