Unleashing the Power of Non-Linearity: Adding Flavor to Language Models

AI Public Literacy Series- ChatGPT Primer Part 3f

The Secret Superpowers Behind ChatGPT's Chat Skills

ChatGPT's human-like conversational ability is powered by neural networks with key components called activation functions.

Let's uncover how these functions enable its impressive language skills!

What Do Activation Functions Do?

A neural network consists of layers of neurons or "switches" that turn on and off.

Activation functions decide which switches to flip by converting input signals into output values between 0 and 1 or -1 and 1.

Any output over a set threshold means the neuron switch turns on.

This allows the neuron to activate and pass data to the next layer in the network. So the activation function controls the on/off patterns.

Activation Function All-Stars

Some common activations include:

  • Sigmoid - The original switch, now rarely used due to downsides.

  • ReLU - Rectified Linear Unit introduces sparsity, is simple and widely used.

  • LeakyReLU - A ReLU variant that allows small non-zero gradients, preventing "dying neurons".

  • Swish - A smooth, lightning-fast switch suited for many applications.

  • GELU - Gaussian Error Linear Unit optimized for NLP uses like chatbots.

Why Are They Crucial?

Stacking many layers with carefully chosen activation functions allows networks to estimate extremely complex relationships and patterns.

This layering of different on/off neuron patterns enables modeling the nuanced complexities of language like semantics, context, sarcasm.

Activations also impact how well networks train on massive datasets. For example, GELU optimizes training ChatGPT on huge volumes of text data.

The Takeaway

Activation functions flip neuron switches in clever sequences to model intricate relationships.

This enables ChatGPT to grasp language nuances and train on massive text data, unlocking its impressive conversational abilities!