The learning loop

Step a line through predict, measure, find the direction, and update, and watch training and test loss fall.

BeginnerExplained in The learning loop

The learning loop

A model (the line) improves by repeating four steps. Step through one round at a time, or let it run.

1PredictUse the current line to guess y for every training x.
2Measure the lossAverage the squared misses into one number.
3Find the directionWork out which way to nudge w and b to lower the loss.
4UpdateMove w and b a small step that way. Repeat.

Training points (used to learn)
Test points (held back)
Current line

The line starts out wrong. Press Next step to begin the first round.

Step size (learning rate)0.50

How far each update moves w and b.

Round0

Training loss0.1007

Test loss0.0858

Slope w-0.5

Intercept b0.85

Try this

Step through one full round with Next step and read each note.
Run with a small step size, then with the largest. Compare the loss curves.