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arXiv · 2409.19561

Unifying back-propagation and forward-forward algorithms through model predictive control

Lianhai Ren·Qianxiao Li
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Abstract

We introduce a Model Predictive Control (MPC) framework for training deep neural networks, systematically unifying the Back-Propagation (BP) and Forward-Forward (FF) algorithms. At the same time, it gives rise to a range of intermediate training algorithms with varying look-forward horizons, leading to a performance-efficiency trade-off. We perform a precise analysis of this trade-off on a deep linear network, where the qualitative conclusions carry over to general networks. Based on our analysis, we propose a principled method to choose the optimization horizon based on given objectives and model specifications. Numerical results on various models and tasks demonstrate the versatility of our method.

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Lianhai Ren, Qianxiao Li. 2024-09-29. Unifying back-propagation and forward-forward algorithms through model predictive control. https://arxiv.org/abs/2409.19561

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