An ensemble combines predictions from multiple models to improve accuracy. Instead of training many neural networks independently, cosine annealing can produce several model snapshots from one training run. section 5.2.3
Cosine-annealing snapshots provide a practical ensemble workflow:
- Train one model with a learning rate that repeatedly decreases to a small value and rises again. section 5.2.3
- Copy the weights whenever the learning rate reaches the bottom of a dip; each copy becomes one ensemble member. section 5.2.3
- For 20 snapshots over T epochs, set Tmax = T/(20·2−1) to obtain 20 dips. section 5.2.3
- Use stochastic weight averaging to average parameters into one model with ensemble-like accuracy and the storage cost of one model. section 5.2.3
Snapshot ensemble
A 20-network ensemble would normally require training and storing 20 networks. Cosine annealing instead stores weights at 20 learning-rate minima during one run, then averages their predictions. section 5.2.3










