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Reading workspace demo

Why a learning rate can feel fast and still learn slowly

6 minute guided experiment

Build the mental model

Gradient descent repeatedly asks one local question: which direction makes the loss smaller from where the model is now? The learning rate decides how much confidence to place in that answer.

A tiny step usually moves in the right direction, but may need many updates. A large step covers more ground, but the slope can change before the optimizer lands. The useful setting is therefore not “as large as possible”; it is large enough to make progress without destroying the signal.

Read the loss curve

The curve below is deliberately simple. Its minimum sits at zero and the slope gets steeper as the parameter moves away from that point. This lets you isolate the behavior of the optimizer before adding the complexity of a real network.

Run the experiment

Start near 0.18, then increase the learning rate. Look at the path between points, not only the final loss. Oscillation is visible before it becomes catastrophic.

Live concept
loss = 1.0
0510152025012345parameter value (x)

Tune gradient descent

Change the learning rate and iteration count. Watch the optimizer settle, oscillate, or overshoot the minimum.

Convergingloss 0.014

The optimizer is moving efficiently.

Take it further

Real loss landscapes have many dimensions, noisy gradients, and changing curvature. The same intuition still transfers: observe the update path, choose a stable scale, and use schedules or adaptive optimizers when one global step size cannot serve every stage of training.