Gather round, Twitter folks, it's time for our beloved
**Alice's adventures in a differentiable wonderland**, our magical tour of autodiff and backpropagation. π₯
Slides below 1/n π
It all started from her belief that "very few things indeed were really impossible". Could AI truly be below the corner? Could differentiability be the only ingredient that was needed?
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Wondering were to start, Alice discovered a paper by pioneer @ylecun promising "a path towards autonomous intelligent agents".
Intelligence would arise, it was argued, by several interacting modules, were everything was assumed to be *differentiable*.
A new method to sample structured objects (eg, graphs, sets) with a formulation inspired to the state space of reinforcement learning.
I have collected a few key ideas and pointers below if you are interested. π
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*Flow Network based Generative Models for Non-Iterative Diverse Candidate Generation* #NeurIPS paper by @folinoid@JainMoksh et al. introducing the method.
The task is learning to sample objects that can be built 1 piece at a time ("lego-style").
To a practical course, a practical exam: I asked each student to include a new branch in the repository showcasing additional tools and libraries.
The result? *Everyone* loves some hyper-parameter optimization. π
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Thanks to their work, you'll find practical examples of fine-tuning parameters using @OptunaAutoML, AX (from @facebookai), @raydistributed Tune, and Auto-PyTorch and Talos coming soon.
An emerging approach in generative modelling that is gathering more and more attention.
If you are interested, I collected some introductive material and thoughts in a small thread. π
Feel free to weigh in with additional material!
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An amazing property of diffusion models is simplicity.
You define a probabilistic chain that gradually "noise" the input image until only white noise remains.
Then, generation is done by learning to reverse this chain. In many cases, the two directions have similar form.
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The starting point for diffusion models is probably "Deep Unsupervised Learning using Nonequilibrium Thermodynamics" by @jaschasd Weiss @niru_m@SuryaGanguli
*LocoProp: Enhancing BackProp via Local Loss Optimization*
by @esiamid@_arohan_ & Warmuth
Interesting approach to bridge the gap between first-order, second-order, and "local" optimization approaches. π
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The key idea is to use a single GD step to define auxiliary local targets for each layer, either at the level of pre- or post-activations.
Then, optimization is done by solving local "matching" problems wrt these new variables.
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What is intriguing is that the framework interpolates between multiple scenarios: first solution step is the original GD, while closed-form solution (in one case) is similar to a pre-conditioned GD model. Optimization is "local" in the sense that it decouples across layers.