Understanding Transformers In A Simple Way With A Clear Analogy

How Transformers Revolutionize Natural Language Processing and Why They Are Superior to Previous Techniques

Sebastien Callebaut
3 min readMay 16, 2024

Transformers have revolutionized natural language processing, offering significant improvements over previous techniques such as recurrent neural networks (RNNs) and convolutional neural networks (CNNs). While their complexity can seem daunting, transformers provide a powerful and efficient means of analyzing and generating human language. In this article, we aim to demystify transformers by providing a simple analogy to help readers better understand their mechanisms and advantages. By the end, you’ll see why transformers are superior to earlier methods and why there’s no need to be intimidated by them.

Photo by Steve Johnson on Unsplash

1. Input Representation (Embedding)

The detective agency receives a message written in a foreign language (raw input text). They need to translate it into a common language (embeddings) that all detectives understand. This is done by converting words into numerical representations.

2. Positional Encoding

Since the order of clues is important, the agency notes the position of each clue in the message. This helps the detectives understand the sequence in which the clues were presented.

3. Attention Mechanism

Detectives work in teams (multi-head attention). Each team focuses on different parts of the message, looking for connections between clues. They then share their findings with each other.

4. Self-Attention

Within each team, detectives cross-check all clues with each other (self-attention) to identify which clues are related. This helps them understand the context and significance of each clue.

5. Feedforward Neural Networks

After gathering insights, detectives analyze the clues further using their own experience and logic (feedforward neural networks). Each detective processes the clues individually to come up with possible interpretations.

6. Layer Normalization and Residual Connections

Detectives regularly summarize their findings and check them against the initial clues (residual connections). They also ensure their conclusions are consistent and standardized (layer normalization).

7. Stacking Layers

This process of cross-checking, analyzing, and summarizing is repeated several times (stacking transformer layers), with each layer refining the previous layer’s work.

8. Output Representation

Finally, the agency translates their solved mystery back into the foreign language (output representation), delivering the final result (output text) to the client in a comprehensible format.

9. Training (For New Cases)

For ongoing training, detectives review previous cases, learn from mistakes, and update their strategies (training with backpropagation and optimization).

Summary

  • Input Representation: Translating foreign clues.
  • Positional Encoding: Noting the sequence of clues.
  • Attention Mechanism: Teams focusing on different parts.
  • Self-Attention: Cross-checking clues within teams.
  • Feedforward Networks: Individual analysis by detectives.
  • Layer Normalization/Residual Connections: Summarizing and standardizing findings.
  • Stacking Layers: Refining analyses through multiple reviews.
  • Output Representation: Translating solved mysteries back.

Conclusion

Transformers represent a major leap forward in natural language processing by addressing the limitations of previous techniques. Unlike RNNs and CNNs, transformers can process entire sentences at once, capturing long-range dependencies and improving learning efficiency. Through our simple analogy, we’ve broken down the key steps of transformers — input representation, positional encoding, attention mechanisms, and more — into easily understandable concepts. This approach demonstrates how transformers efficiently handle complex textual data, making them a revolutionary tool in the field. By simplifying these concepts, we hope to show that transformers are not as intimidating as they might initially appear, and their powerful capabilities are accessible and beneficial for a wide range of applications.

--

--

Sebastien Callebaut

Using data and coding to make better investing decisions. Co-founder of stockviz.com