rrelu
**RReLU** (Randomized Leaky ReLU) is a **variant of Leaky ReLU where the negative slope is randomly sampled from a uniform distribution during training** — and fixed to the mean of that distribution during inference, providing built-in regularization.
**Properties of RReLU**
- **Training**: $ ext{RReLU}(x) = egin{cases} x & x > 0 \ a cdot x & x leq 0 end{cases}$ where $a sim U( ext{lower}, ext{upper})$ (typically $U(0.01, 0.33)$).
- **Inference**: $a = ( ext{lower} + ext{upper}) / 2$ (deterministic).
- **Regularization**: The randomness during training acts as a stochastic regularizer (similar to dropout).
- **Paper**: Xu et al. (2015).
**Why It Matters**
- **Built-In Regularization**: The random slope provides implicit regularization without explicit dropout.
- **Kaggle**: Popular in competition settings where every bit of regularization helps.
- **Simplicity**: No learnable parameters (unlike PReLU), but with regularization benefits.
**RReLU** is **the stochastic ReLU** — introducing randomness in the negative slope for built-in regularization during training.