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Learn machine learning · part 9 · session 2

One step, one distribution

Given the text so far, the model produces one score for every character in its vocabulary, a full set of odds for what comes next, adding up to 1. It computes nothing beyond that one step.

After this session you will be able to read a next-character distribution and say what temperature does to it.

next.tokenSession 9.2About 40 minutesYour check: demonstrate the idea yourself

To pass: produce the target string exactly, with every character selected from the distribution list rather than sampled, and the right call on why five runs differ.

01 · The question

This model was trained by a script in the repository, not in your browser, and it predicts the next character rather than the subword tokens you built in the last session. Production models work on subword tokens, for the reason that session showed, and the operation is the same one either way: . One step takes a prompt of at most 64 characters and returns one number for every character in the vocabulary. On this page you are the sampler: read the distribution and pick, or hand the pick to and see what it costs you.

The model has about 112,000 numbers inside, which is tiny.

The bundled model's shape

2 blocks, d = 64, 4 heads, context 64, a 64-character vocabulary, about 112,000 parameters, stored as int8 with per-row scales.

The Wonderful Wizard of Oz, L. Frank Baum (1856-1919), 1900. Public domain.

02 · Predict

Before anything runs

After the prompt `the `, how much probability will the single most likely next character hold?

After the prompt `the `, how much probability will the single most likely next character hold?

Choose something first.

03 · Try it

Steer it to the target

Each target came out of this model at the temperature recorded in the file under a recorded seed, so every character of it is inside the top twelve at its own step. Leaving the target is allowed: the matched count drops and nothing is blocked.

One step at a time

computed in this browserweights trained offline by the course script

Loading the bundled model.

Every chatbot you have used is this loop: produce the odds, pick one piece, put it back on the end of the input, produce the odds again.

What a language model does

computed in this browserone forward pass, weights trained offline by the course script

The text so far sits in a slot.

One step: odds, pick, append, then again.

Five seeds at temperature 1

Five seeds, one prompt

computed in this browsertemperature 1

No continuations drawn yet.

Why they differ

Why do five runs at temperature 1 produce five different continuations?

Call the reason before you submit.

04 · Compare

Submit the run and the verdict lands here, against the position you took above.

05 · Check your understanding

Your check: an outcome you produce

not yet

In one submission: the produced continuation matches the target string exactly, every appended character was selected from the distribution list rather than sampled, and the multiple-choice reason is correct.

Not met yet. Keep working the session.

Where you are

  • Target matched: not yet.
  • Sampled characters in the run: 0.
  • The reason: not called yet.

Ask for a hint

Rungs open as you run the session, not as time passes. You have run it 0 times.

1. A question about your own trace: available after 3 evaluated runs.

2. The list is never the problem: available after 5 evaluated runs.

3. A different example, computed in full: available after 7 evaluated runs.

4. The full pick sequence: available after 9 evaluated runs.

Save your takeaway

Your takeaway

Edit it into your own words, or keep the line as it is.

9.5 sorts your own trace beside samples from two other sizes, and 10.3 lets the decoding slot cite it.