Chess GPT learning lab · Field notebook 00

Predict before
you train.

Learn machine learning by forecasting what each lever will do, testing it on a real chess model, and explaining the evidence.

The learning contract

Understanding has observable evidence.

01

Forecast

State direction, magnitude, assumptions, confidence, and likely failure modes.

02

Discriminate

Choose the best implementation and explain why the alternatives fail.

03

Measure

Run one controlled change against a trustworthy baseline.

04

Update

Explain surprises from memory and revise the mental model.

The complete path

Ten causal questions.

Ten chapters form the core. A four-part reinforcement-learning extension follows once the supervised model and evaluation protocol are trustworthy.

02

How can a number learn?

Turn prediction errors into useful parameter changes.

Hill climbing · loss · gradientsLocked
03

How do moves become probabilities?

Generalize beyond histories seen word-for-word.

Tensors · embeddings · softmaxLocked
04

Did it learn or memorize?

Know whether improvement will survive unseen games.

Capacity · overfitting · regularizationLocked
05

How fast should it learn?

Use the budget quickly without destabilizing training.

Learning rate · batches · AdamWLocked
06

How can any earlier move matter?

Reach relevant context anywhere in the game history.

Attention · position · causal masksLocked
07

What makes a Transformer trainable?

Assemble a stable model within the size limit.

Residuals · normalization · depthLocked
08

How should we spend the budget?

Allocate 100 MB and one exaFLOP deliberately.

Precision · FLOPs · scalingLocked
09

Does lower loss mean stronger chess?

Select for wins, not attractive training curves.

Calibration · matches · EloLocked
10

How does an idea become evidence?

Make creative experiments credible and useful.

Hypotheses · ablations · reproducibilityLocked

Phase II · optional competitive extension

Reinforcement learning

RL asks a different question: not “what move did a human play?” but “which action improves expected game result?” Self-play only reaches the tournament model after the shared-data rule is clarified.

R1

When is prediction the wrong objective?

Separate imitating human moves from maximizing game result.

Policy · reward · returnLocked
R2

How does a win teach earlier moves?

Assign credit when the clearest signal arrives at checkmate.

Value · Bellman · Monte Carlo · TDLocked
R3

Should we learn values, actions, or both?

Choose an algorithm family that fits chess and the budget.

Policy gradients · actor-critic · explorationLocked
R4

Can self-play improve us honestly?

Control opponent drift, variance, compute, and evaluation bias.

Self-play · search · paired matchesLocked

Placement diagnostic · 10–15 minutes

Show me how you reason today.

No preparation and no pass mark. Answer without searching, record your confidence, then submit once. Your result determines the starting path for Chapter 1.

Important: a confident wrong answer is more useful for teaching than a disguised guess.
Q01Read a loop

What is the final value of best?

scores = [2, 5, 1]
best = scores[0]
for score in scores:
    if score > best:
        best = score
How confident are you?
Q02Read a loss

The played move was Nc6. Model A assigned it probability 0.8; Model B assigned 0.2. Which model has lower negative log-likelihood?

How confident are you?
Q03Follow a gradient

For L(w) = (w − 3)² at w = 1, the derivative is −4. A small gradient-descent step moves w in which direction?

How confident are you?
Q04Change a lever

The learning rate becomes 100× larger and updates repeatedly overshoot the minimum. What is the most likely training behaviour?

How confident are you?
Q05Change a split

A fixed dataset changes from 10% to 40% validation data. What trade-off should you predict?

How confident are you?
Q06Change capacity

Model width increases substantially while data and training stay fixed. What is the safest initial prediction?

How confident are you?
Q07Read a shape

A batch has 32 games, 16 moves of context, and 64 values per move embedding. What is the resulting tensor shape?

How confident are you?
Q08Choose a protocol

Which workflow preserves an honest final estimate while still allowing model selection?

How confident are you?
0 answers · 0 confidence ratings8 decisions remain

The source shelf

Primary sources, assigned with purpose.