metainit
**MetaInit** is a **meta-learning-based initialization method that uses gradient descent to find weight initializations that minimize the curvature of the loss landscape** — searching for starting points where training dynamics will be most favorable.
**How Does MetaInit Work?**
- **Objective**: Find initial weights $ heta_0$ that minimize the trace of the Hessian $ ext{tr}(H( heta_0))$ (surrogate for loss landscape curvature).
- **Process**: Use gradient descent on the initialization itself — not on the loss, but on a meta-objective about the loss landscape.
- **Effect**: Produces starting points in flat, well-conditioned regions of the loss landscape.
- **Paper**: Dauphin & Schoenholz (2019).
**Why It Matters**
- **Principled**: Directly optimizes the quantity that determines training difficulty (curvature).
- **BatchNorm-Free**: Can enable training of deep networks without BatchNorm by finding better starting points.
- **Theory**: Connects initialization to the loss landscape geometry literature (flat vs. sharp minima).
**MetaInit** is **learning how to start** — using meta-learning to find the optimal initial conditions for neural network training.