Student Guide to Generative AI

Generative AI, particularly through Large Language Models (LLMs), leverages machine learning to create new content like text, images, or even code, based on existing data. Machine learning enables these models to learn patterns and structures from vast datasets, allowing them to generate novel content that resembles the training data.

• What is generative AI?

  • It’s AI that can generate new content, like text, images, video, music, and speech. Some examples of models that generate text are ChatGPT, Microsoft Copilot, and Google Gemini. Models like MidJourney, Adobe Firefly, and Stable Diffusion can generate images. For generating speech, Eleven Labs is a popular tool. Suno and Udio are models for generating music.

    Another type of AI is “discriminative AI.” That’s AI that can classify, predict, or recognize patterns in existing data. Some examples are Netflix’s recommendations for what to watch next and Gmail’s spam filtering.

    It’s good to keep these two types in mind when you hear about AI. Is it classifying existing data (like with spam filtering), or is it generating new content (like with ChatGPT)? These are very different types of systems with different strengths and weaknesses.

• What is machine learning? 

  • Machine learning is the practice of developing computer models that can learn patterns and improve their performance based on input data. This allows the model to make predictions based on the patterns it’s learned. It can solve problems without being explicitly programmed for each task. This is very different from rules-based programming where programmers lay out each step for the machine to follow. Instead, these models learn from patterns.

• What is a large language model (LLM)?

  • A large language model (LLM) is a type of artificial intelligence that can generate human language and perform related tasks. These models are trained on huge datasets, often containing billions of words. By analyzing all this data, the LLM learns patterns and rules of language, similar to how a human learns to communicate through exposure to language. LLMs can perform various language tasks, such as answering questions, summarizing text, translating between languages, and writing content.

    Some examples of LLMs include ChatGPT, Claude, Microsoft Copilot, Gemini, and Meta AI.

    Since language models are now becoming multimodal (working with media types beyond text), they are now also called “foundation models”. This refers to models that are trained on vast amounts of data and can be adapted to a wide range of tasks and operations, , not just working with language.

• What is "hallucination" in generative AI tools?

  • Hallucination is the word used to describe the situation when models like ChatGPT output false information as if it were true. Even though the AI may sound very confident, sometimes the answers it gives are just plain wrong. 

    Why does this happen? AI tools like ChatGPT are trained to predict what words should come next in the conversation you are having with it. They are really good at putting together sentences that sound plausible and realistic.

    However, these AI models don't understand the meaning behind the words. They lack the logical reasoning to tell if what they are saying actually makes sense or is factually correct. They were never designed to be search engines. Instead they might be thought of as “wordsmiths”—tools for summarizing, outlining, brainstorming, and the like.

    So we can't blindly trust that everything they say is accurate, even if it sounds convincing. It's always a good idea to double check important information against other reliable sources.

    Here’s a tip: Models that are grounded in an external source of information (like web search results) hallucinate less often. That’s because the model searches for relevant web pages, summarizes the results, and links to the pages that each part of the answer came from. This makes it easier to fact-check the result.

    Examples of grounded models are Microsoft Copilot, Perplexity, and ChatGPT Plus (the paid version).