arXiv:2509.10973cs.LGcs.AI2025-09

通过解耦表示空间搜索与参数空间学习,提升模型泛化能力

Decoupling Search and Learning in Neural Net Training

  • 先在中间激活空间搜索多样解,再用梯度回归到这些解
  • 搜索计算越多,解越优且多样,性能逼近SGD基准
  • 适合研究如何突破梯度下降探索局限的算法设计者

梯度下降通常收敛到单一极小值,缺乏探索可能泛化更好的替代极小值的机制。直接在高维参数空间中搜索多样极小值通常不可行。为此,我们提出一个双阶段训练框架:第一阶段在可处理的表示空间(中间激活空间)进行搜索,发现多样化的表征解;第二阶段通过回归到这些搜索所得的表征,在参数空间中进行基于梯度的学习。通过进化搜索,我们发现其适应度和多样性随计算量增长——更大种群和更多代数产生更优且更丰富的解。这些表征可被学习:回归到这些表征的网络在MNIST、CIFAR-10和CIFAR-100上接近SGD性能,且性能随搜索计算量提升直至饱和。所得模型在训练过程中表现出不同的表征轨迹,与传统梯度下降训练的模型有本质差异。该工作表明,未来训练算法可通过解耦表示空间的搜索与参数空间的高效梯度学习,克服梯度下降的探索限制。

原文摘要 · Abstract (English)

Gradient descent typically converges to a single minimum of the training loss without mechanisms to explore alternative minima that may generalize better. Searching for diverse minima directly in high-dimensional parameter space is generally intractable. To address this, we propose a framework that performs training in two distinct phases: search in a tractable representation space (the space of intermediate activations) to find diverse representational solutions, and gradient-based learning in parameter space by regressing to those searched representations. Through evolutionary search, we discover representational solutions whose fitness and diversity scale with compute--larger populations and more generations produce better and more varied solutions. These representations prove to be learnable: networks trained by regressing to searched representations approach SGD's performance on MNIST, CIFAR-10, and CIFAR-100. Performance improves with search compute up to saturation. The resulting models differ qualitatively from networks trained with gradient descent, following different representational trajectories during training. This work demonstrates how future training algorithms could overcome gradient descent's exploratory limitations by decoupling search in representation space from efficient gradient-based learning in parameter space.

神经网络训练优化表示学习

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。