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I broke into professional industry machine learning at 18. I'm gonna be talking to you about a model that you probably have not heard of called symbolic regression. And I know many industry professionals and data scientists that do not know about it either. So don't be scared if you don't. This is a model that's mainly used in, like, physics simulations and biology and quantitative finance. So here's the thing, right? Most machine learning works like this. You tell the computer what shape the answer should be, and it fills in the numbers. Like with linear regression, you already have the equation. You're just trying to find constants to multiply your data points with to fit that line. Your computer is only working out which line out of all the lines you decided, right? So basically, every model you've heard of is like that. You pick the shape, and it fills in the blanks. Symbolic progression doesn't get told the shape. It works that out, too. And what it hands back is a proper equation, the kind that you see in a textbook. So it's not looking for just constants. It's actually looking for a math equation, too. Here's how. And it's honestly just evolution. So it starts by writing a few hundred completely random equations. They're all crap and rubbish, and it scores each one on how close it gets and deletes the worst and breeds the survivors. It's called, um, genetic programming. Like survival of the fittest, it takes a chunk of one equation and splits it into another and randomly swaps a plus for a times. Then it does it again and again and again, thousands of times. Now, bad equations die out. The bits that work get passed on. Same as evolution, except it takes a minute instead of a billion years. So I tested it properly. I made up an equation, first number squared minus the second number plus 1, and generated 500 data points from it. Then I deleted the equation and handed over nothing but the points. Now you're about to see the equation that it actually found in row three there. That's mine. Exactly. It worked it out just from the data alone. And here's a bit that actually matters. I trained a normal machine learning model on that same data. Then I tested both of them on numbers neither had ever seen. So the normal one falls apart. Like, look at this. 300 different inputs, and it gives the same answer to all of them because all it ever learned was how to copy patterns it had already been shown. But the equation just keeps working because it's an equation. It doesn't have an edge. This was the whole appeal. Most models learn to imitate your data, but this one actually learns the rule underneath it. And you're probably like, Iris, why don't we just use symbolic regression then? The thing is, it's a really costly approach because you're trying to basically make it shape up all of the possibilities out of this like huge space of different mathematical expressions. So actually it suffer from combinatorial explosion. But the trade off is that training is slow, but actually using the model to predict something is fast by an inference. Essentially we'd use symbolic regression for smaller data sets that are very, very niche. However, there are hybrid approaches that come out. So for example, a transformer like looks at the dataset and predicts the most likely equation skeleton in a single pass. So there are workarounds around it. And I think this is a pretty cool model, to be honest. But yeah, I think this is really cool. And I think if you are really into more of the mathematical side, not saying machine learning isn't, but this is actually quite cool. And it's quite a niche thing if you wanna spice up your portfolio.