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Lesson 4
20 min

Training Data, Loss, and Gradient Descent (Plain English)

Quick Summary

Training data supplies examples, a loss function measures error, and gradient descent guides small weight updates. Together they define what the model is rewarded for learning.

What you will learn
  • Explain the roles of training, validation, and test data
  • Describe loss as a measurement of model error
  • Use a plain-language analogy for gradient descent
Intermediate Content

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Training Data, Loss, and Gradient Descent (Plain English) is part of How AI Actually Works (Under the Hood) — an intermediate module. We keep these gated so we can save your progress, recommend next steps, and personalize the curriculum.

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