How linear regression works intuitively and how it leads to gradient descent

Learning, to a computer, is just turning bad guesses into better ones. In this post, we’ll see how that starts with a straight line: how linear regression makes the first guess, and gradient descent keeps improving it. Let's start with something familiar: house prices. Bigger houses tend to cost more; smaller ones, less. It's the kind of pattern you can almost see without thinking: more space, more money. When we plot it, the shape is clear: a loose upward slope, with some noise but a definite trend. As you can see, price and size move together in a way that feels predictable. Not in fixed steps or categories, but on a sliding scale. A house might go for $180,000, $305,500, or anything in between. Now imagine you're selling your own house. It's 1,850 square feet—larger than average, but not a mansion. You've seen what homes go for in your area, but the prices are scattered. What's a fair number to list it at? One option is to text your real estate friend and get a half-baked guess ... Read full article.