Course: Introduction to Generative AI for Technical Managers and Executives

Chapter 1: Understanding the Foundations of Generative AI Models

The cornerstone model architecture for the entire suit of Generative AI / Large Language Models is called Transformer models.

1.1 Introduction to Transformer Architecture

Transformers are a type of deep learning model primarily used in natural language processing (NLP) but have found applications in various domains due to their powerful ability to handle sequential data. The transformer architecture consists of two main components: the encoder and the decoder.

  • Encoder: The encoder processes the input sequence and converts it into a set of continuous representations. It consists of multiple layers, each with two sub-layers: a multi-head self-attention mechanism and a position-wise fully connected feed-forward network. The encoder’s role is to capture the contextual information of the input sequence.
  • Decoder: The decoder generates the output sequence from the encoded representations. Like the encoder, the decoder also consists of multiple layers, each containing a multi-head self-attention mechanism, a multi-head attention mechanism that attends to the encoder’s output, and a position-wise fully connected feed-forward network. The decoder produces the final output sequence by predicting one token at a time.

1.2 Types of Generative Models

  1. Autoregressive Models: These models generate each token in the sequence one at a time, using the previously generated tokens as context.
    • Example: GPT (Generative Pre-trained Transformer)
    • Use Case: Language generation tasks such as text completion, chatbot responses, and creative writing.
  2. Autoencoding Models: These models encode the input into a latent representation and then decode it back to reconstruct the original input.
    • Example: BERT (Bidirectional Encoder Representations from Transformers)
    • Use Case: Tasks requiring understanding and representation of the input, such as text classification, sentiment analysis, and named entity recognition.
  3. Sequence-to-Sequence (Seq2Seq) Models: These models are used for transforming one sequence into another sequence, often employing an encoder-decoder architecture.
    • Example: T5 (Text-To-Text Transfer Transformer)
    • Use Case: Translation, summarization, and any task that involves mapping input sequences to output sequences.
  4. Multimodal Models: These models can process and generate data across multiple modalities, such as text, images, and audio.
    • Example: DALL-E (Generative Model for Images from Text Descriptions)
    • Use Case: Tasks that require understanding and generating content from multiple data types, such as generating images from textual descriptions or vice versa.
  5. Retrieval-Based Models: These models generate responses by retrieving the most relevant information from a pre-existing dataset.
    • Example: RAG (Retrieval-Augmented Generation)
    • Use Case: Information retrieval tasks where the goal is to find and present the most relevant data from a large corpus, such as question-answering systems and chatbots that rely on existing knowledge bases.

1.3 Examples and Use Cases

  1. GPT (Autoregressive)
    • Example: Generating a news article based on a headline.
    • Use Case: When you need coherent and contextually relevant text generation over a sequence.
  2. BERT (Autoencoding)
    • Example: Sentiment analysis of product reviews.
    • Use Case: When you need to understand the contextual meaning of the text for classification or other understanding-based tasks.
  3. T5 (Seq2Seq)
    • Example: Translating a document from English to French.
    • Use Case: When you need to convert input sequences to a different format, such as language translation or text summarization.
  4. DALL-E (Multimodal)
    • Example: Creating an image of a “two-story pink house shaped like a shoe” based on a text description.
    • Use Case: When generating visual content from textual descriptions, or integrating multiple data types for creative and practical applications.
  1. RAG (Retrieval-Based)
    • Example: Answering a question about historical events using a large database of documents.
    • Use Case: When the goal is to provide accurate and contextually relevant information from a large corpus, ideal for knowledge-based systems.

1.4 Choosing the Right Model with Practical Use Cases

Let’s take 3 different domains for our example use cases – Cybersecurity, Healthcare and Finance.

  • Autoregressive Models
    • Cybersecurity: Generating detailed reports of security incidents by summarizing logs and alerts.
    • Healthcare: Generating patient discharge summaries from medical notes.
    • Finance: Creating personalized financial advice based on historical transaction data.
  • Autoencoding Models
    • Cybersecurity: Anomaly detection by understanding the typical behavior of network traffic and identifying deviations.
    • Healthcare: Classifying medical images to detect anomalies or diseases.
    • Finance: Fraud detection by analyzing transaction patterns and identifying unusual activities.
  • Seq2Seq Models
    • Cybersecurity: Translating technical threat descriptions into layman’s terms for broader communication.
    • Healthcare: Converting electronic health records (EHR) into standardized formats.
    • Finance: Automating the generation of financial reports from raw transaction data.
  • Multimodal Models
    • Cybersecurity: Integrating text-based threat reports with visual network diagrams for comprehensive analysis.
    • Healthcare: Generating medical diagnoses by combining patient records (text) with medical imaging (images).
    • Finance: Creating financial dashboards by integrating textual analysis of market reports with graphical data representations.
  • Retrieval-Based Models
    • Cybersecurity: Providing real-time, relevant information from a knowledge base to respond to detected threats.
    • Healthcare: Offering quick access to relevant medical literature for specific patient symptoms or conditions.
    • Finance: Answering customer queries by retrieving the most relevant information from a financial knowledge base.

Summary

In this chapter, we’ve covered the basics of transformer architecture, differentiating between the encoder and decoder. We discussed five types of generative models: autoregressive, autoencoding, seq-to-seq, multimodal, and retrieval-based, providing examples and practical use cases across cybersecurity, healthcare, and finance domains. Understanding these fundamentals will help you choose the appropriate model for various generative AI tasks in different industries.