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How a Machine Learns: Reducing Error

Learning is trial and error with feedback. The model makes a guess, a loss number measures how wrong it is, and a small change is made to the model to reduce the loss. Repeat thousands of times. Moving in the direction that lowers the loss is called gradient descent.

Here is a one-number model: guess the multiplier w in y = w * x from examples where the true rule is y = 3x.

Examplepython
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Quick check

What does the loss measure?

Your turn: write the code

Run 20 steps of the same learning loop and print w rounded to 2 decimals.

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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