Posts

Orthogonality & Orthonormal Basis Explained (Linear Algebra for Developers)

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Upgrade Your Basis: The Power of Orthogonality in Machine Learning In our last video, we discovered the Basis —the "ultimate Lego kit" for our data. We learned that any set of linearly independent vectors can define a coordinate system for a space. But this leads to a critical engineering question: are all bases created equal? The answer is a firm no. A skewed, inefficient basis works, but it makes calculations awkward and complex. Intuitively, we know that a clean, 90-degree coordinate system is better. To formalize this intuition, we need to upgrade our basis using the concepts of Orthogonality and Normalization . In this post, we'll decode the math behind the "gold standard" of coordinate systems, the Orthonormal Basis, and show why it's the preferred toolkit for engineers and data scientists. Watch the video for the full visual explanation, then scroll down for the detailed definitions and code. T...

Finding the True Dimension of Your Data (Basis & Rank Explained)

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From Chaos to Order: Finding the Basis of Your Data Imagine you have a dataset with hundreds of features, each represented as a vector. This collection of vectors can describe a vast, high-dimensional world of possibilities. But is this the most efficient way to describe that world? Do we really need hundreds of vectors if the underlying structure is much simpler? This leads to a fundamental engineering question: What is the smallest possible set of building blocks we need to describe our entire data space without losing any information? The answer lies in the elegant concepts of Span, Basis, and Dimension . In this post, we'll decode these concepts to build a powerful mental model for understanding the true "shape" and complexity of your data. Watch the video for the full visual explanation, then scroll down for the detailed definitions and examples. The "Playground": Generating Sets and Span Let...

A Developer's Guide to Vector Embeddings (Text & Images)

A Developer's Guide to Vector Embeddings: The Secret to "Meaning" in AI How can a computer, a machine that only understands numbers, possibly solve an analogy like King - Man + Woman = Queen ? It seems like magic. It's not. It's the result of one of the most powerful and important concepts in modern machine learning: Vector Embeddings . Embeddings are the engine behind everything from ChatGPT's language understanding to your Netflix recommendations. In this post, we are going to decode embeddings from first principles. We'll build the developer's mental model for what they are, how they are created, and why they are so fundamental to modern AI systems. The Big Idea: Translating Meaning into Geometry At its core, a vector embedding is a translator . It takes a discrete, non-mathematical item (like a word, a movie, or a product) and translates it into a list of numbers—a vector—in a high-dimensional space. ...

Linear Independence & Dependence Explained (The Key to Feature Engineering)

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This is Why Your Machine Learning Model is Unstable (Linear Independence) Imagine you're building a machine learning model to predict a person's weight. You have a dataset with features like height in centimeters and age. To improve the model, you decide to add another feature: height in inches. Your intuition might say "more data is better," but as an engineer, you should spot the flaw immediately. The "height in inches" feature is 100% redundant . It provides zero new information that "height in centimeters" doesn't already. This common-sense idea of redundancy has a formal, powerful name in linear algebra: Linear Dependence . Understanding the difference between linear dependence and independence is not an abstract academic exercise; it's a critical concept with huge real-world consequences for building simpler, faster, and more robust ML models. Watch the video for the full visual explanation, then scrol...

What is a Vector Space? (The Math That Powers Word2Vec)

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Vector Spaces: The "Playground" Where Your Data Lives How does a computer understand that the word 'King' is related to 'Man' in the same way that 'Queen' is related to 'Woman'? Computers don't understand abstract meaning; they only understand numbers and structure. To solve this, we represent our data—words, images, users—not as isolated items, but as points on a special kind of mathematical map with a strict set of rules. This 'map' is called a Vector Space . It's the playground where our data lives, and its rules are what allow machine learning models to perform seemingly magical feats of logic. In this post, we'll build this concept from the ground up, starting with its most fundamental building block. Watch the video for the full visual explanation, then scroll down for the detailed definitions and axioms. The Foundation: What is a Mathematical "Group"? ...

How to Solve Systems of Linear Equations (The Complete Guide)

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How to Truly Solve Linear Equations (The Math & The Code) A system of linear equations isn't just a problem from high school algebra; it's the hidden engine that powers a huge part of machine learning. The goal is simple: find a unique set of values that satisfy all constraints simultaneously. Visually, it's about finding the exact point where the lines cross. But how do we solve this rigorously? This post provides a more detailed breakdown of the two primary methods: the procedural, step-by-step approach of Gaussian Elimination , and the high-level, conceptual solution using the Matrix Inverse . Watch the video for the full visual explanation, then scroll down for the detailed examples and code. The Mathematician's Way: Gaussian Elimination to RREF To solve a system systematically, we first represent it as an Augmented Matrix . This structure combines the coefficients (A) and the constant outcomes (b) into...

What is a Loss Function? Why is it the GPS of AI?

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What is a Loss Function? The GPS for an AI Imagine we've built a robot. Its job is to place an object on a target, but its first few attempts are way off. As engineers, how do we teach this robot to get better? Before we can teach it to improve , we first need a way to tell it exactly how wrong it is. We need to give it a score. In machine learning, this 'score' acts like a GPS, guiding the model towards the correct answer. This guide is called a Loss Function . In this post, we'll decode this critical concept and explore the engineering trade-offs between the two most common types: Mean Absolute Error (MAE) and Mean Squared Error (MSE). Watch the video first for the full visual explanation, then scroll down for the key concepts and analogies. The Core Idea: Giving AI a Score At its heart, a Loss Function is a simple formula that calculates a single number representing how far a model's prediction was from t...