Live demos.
Six small interactive tools, each making a concept I work with feel less abstract. All runs in your browser; nothing is sent anywhere. Touch-friendly on mobile.
Click to add points. The line follows.
The pink line is the least-squares best fit. R² shows how well it explains the variance.
Pull an arm. Thompson sampling will keep up.
Each arm has a hidden reward rate. You play; the bot uses Thompson sampling. Watch posteriors sharpen as evidence accumulates.
Drop points. Watch them cluster.
Click anywhere to add a point. Press Step to advance one iteration of Lloyd's algorithm.
Drag the threshold. Precision vs recall trade.
A simulated binary classifier scored 300 examples. Move the slider to set the decision threshold and see the confusion matrix update.
Type two conversion rates. See if it's real.
Two-proportion z-test. Lift, z-score, p-value, and a plain-English call on whether the difference is statistically significant at α=0.05.
Slide the model complexity. Watch the lesson.
A polynomial of degree d fits a noisy sine. Low d underfits. High d memorises the noise. The sweet spot is usually simpler than you'd think.