**ESPNetv2** is a convolutional neural network that utilises group point-wise and depth-wise dilated separable convolutions to learn representations from a large effective receptive field with fewer FLOPs and parameters.

**Adaptive Masking** is a type of attention mechanism that allows a model to learn its own context size to attend over. For each head in [Multi-Head Attention](https://paperswithcode.com/method/multi-head-attention), a masking function is added to control for the span of the attention. A masking function is a non-increasing function that maps a
distance to a value in $\left[0, 1\right]$. Adaptive masking takes the following soft masking function $m\_{z}$ parametrized by a real value $z$ in $\left[0, S\right]$:

$$ m\_{z}\left(x\right) = \min\left[\max\left[\frac{1}{R}\left(R+z-x\right), 0\right], 1\right] $$

where $R$ is a hyper-parameter that controls its softness. The shape of this piecewise function as a function of the distance. This soft masking function is inspired by [Jernite et al. (2017)](https://arxiv.org/abs/1611.06188). The attention weights from are then computed on the masked span:

$$ a\_{tr} = \frac{m\_{z}\left(t-r\right)\exp\left(s\_{tr}\right)}{\sum^{t-1}\_{q=t-S}m\_{z}\left(t-q\right)\exp\left(s\_{tq}\right)}$$

A $\mathcal{l}\_{1}$ penalization is added on the parameters $z\_{i}$ for each attention head $i$ of the model to the loss function:

$$ L = - \log{P}\left(w\_{1}, \dots, w\_{T}\right) + \frac{\lambda}{M}\sum\_{i}z\_{i} $$

where $\lambda > 0$ is the regularization hyperparameter, and $M$ is the number of heads in each
layer. This formulation is differentiable in the parameters $z\_{i}$, and learnt jointly with the rest of the model.

Adaptive Masking

Adaptive Attention Span in Transformers

ESPNetv2

ESPNetv2: A Light-weight, Power Efficient, and General Purpose Convolutional Neural Network

A **G-GLN Neuron** is a type of neuron used in the [G-GLN](https://paperswithcode.com/method/g-gln) architecture. G-GLN. The key idea is that further representational power can be added to a weighted product of Gaussians via a contextual gating procedure. This is achieved by extending a weighted product of Gaussians model with an additional type of input called side information. The side information will be used by a neuron to select a weight vector to apply for a given example from a table of weight vectors. In typical applications to regression, the side information is defined as the (normalized) input features for an input example: i.e. $z=(x-\bar{x}) / \sigma\_{x}$.

More formally, associated with each neuron is a context function $c: \mathcal{Z} \rightarrow \mathcal{C}$, where $\mathcal{Z}$ is the set of possible side information and $\mathcal{C}=\{0, \ldots, k-1\}$ for some $k \in \mathbb{N}$ is the context space. Each neuron $i$ is now parameterized by a weight matrix $W\_{i}=\left[w\_{i, 0} \ldots w\_{i, k-1}\right]^{\top}$ with each row vector $w\_{i j} \in \mathcal{W}$ for $0 \leq j<k$. The context function $c$ is responsible for mapping side information $z \in \mathcal{Z}$ to a particular row $w\_{i, c(z)}$ of $W_{i}$, which we then use to weight the Product of Gaussians. In other words, a G-GLN neuron can be defined by:

$$
\operatorname{PoG}\_{W}^{c}\left(y ; f_{1}(\cdot), \ldots, f\_{m}(\cdot), z\right):=\operatorname{PoG}\_{w^{c(z)}}\left(y ; f\_{1}(\cdot), \ldots, f\_{m}(\cdot)\right)
$$

with the associated loss function $-\log \left(\operatorname{PoG}\_{W}^{c}\left(y ; f\_{1}(y), \ldots, f\_{m}(y), z\right)\right)$ inheriting all the properties needed to apply Online Convex Programming.

Source	ESPNetv2: A Light-weight, Power Efficient, and General Purpose Convolutional Neural Network
Year	2000
Data Source	Papers with Code archive (CC BY-SA)