Collection
Monty Hall, Simpson, Berkson and base rates: where intuition fails us with numbers.
Apps
Number forensics on the first digit: data points land on a glass log drum whose sector width is log₁₀(1+1/d). Rescaling only turns the drum; body height and .99 prices fail, manipulated expenses give themselves away (Nigrini MAD, χ²).
Data & decisionsTry it
The filter invents the relationship: a light wall sweeps through 3,000 independent applicants, the selected fly onto a stage — and there the regression line falls (r ≈ −0.67). Sum, or, and, causal diagram with collider.
Data & decisionsTry it
Two 3D cities from the same random numbers: uniform body heights against a Pareto skyline whose tallest tower pierces the clouds. α slider, running mean, log-log tail, Lorenz curve, the one-in-a-million outlier.
Data & decisionsTry it
A sales team across two quarters: the best fall back and the weakest catch up without anyone changing anything. A slider for the share of luck shows when this happens and how strongly.
Data & decisionsTry it
One workforce, many surveys: see how far results jump with few answers and why it takes four times as many answers to halve the uncertainty.
Data & decisionsTry it
A wheel of fortune gives a random number, then you estimate a question from working life. 200 simulated colleagues show how strongly the number pulls the estimates and what a counterargument does against it.
Data & decisionsTry it
Rebuild 2.0 (preview): three real cases — kidney stones, Berkeley 1973, exercise & cholesterol. Subgroups as bubbles, equalise the case mix, and a causal panel asking which view is right.
StatisticsTry it
Rebuild 2.0 (preview): Bayes' theorem with prevalence, sensitivity and specificity, prior and posterior on an absolute scale.
StatisticsTry it
Rebuild 2.0 (preview): the same series, every start–end pair as a triangle of returns, distribution of all windows, rebasing to 100 and axis tricks.
Data & decisionsTry it
Rebuild 2.0 (preview): the same risk as relative and absolute risk, natural frequency, odds and betting odds.
Data & decisionsTry it
Rebuild 2.0 (preview): the slide says “A ahead” — opening the look-back morphs the bars into lines and the trend verdict flips. Prior month vs. same month last year, crossings, stock vs. flow.
Data & decisionsTry it
Rebuild 2.0 (preview): live headline against reality, population mosaic with case dots, age structure as confounder up to reversal, Farrington's screening method.
Data & decisionsTry it
Rebuild 2.0 (preview): five scenarios from abstract to invoice audit, flipped cards land in the truth table, resolution with your own choice pattern and an SQL query.
Data & decisionsTry it
Rebuild 2.0 (preview): exact odds via Conway, non-transitivity as a graph on waiting-time rings, waiting-time paradox, matrix of all duels, Monte Carlo, length 3 and 4.
Data & decisionsTry itCollections
Mathematical questions open for decades, for which an AI model proposed solutions in 2026, as interactive apps: understand the problem, experience the result.
24 appsOpen collection
From neurons and gradients to transformers, RLHF and agents: machine learning you can touch.
39 appsOpen collection
DNA, replication, transcription, translation and cell division as explorable 3D models.
11 appsOpen collection
Perspective, ornament, structure and space: how art and architecture work with mathematics.
9 appsOpen collection
Hyperloop, autonomous vehicles, warehouses and conveyors: logistics as interactive simulation.
17 appsOpen collection
Heart, eye, voice, skeleton and nerves: the human body in 3D, layer by layer.
8 appsOpen collection
Planets, stars, black holes and space probes: the cosmos to explore.
6 appsOpen collection
Riemann, P vs NP, Poincaré and other great questions of mathematics, made tangible.
16 appsOpen collection
Counting, arithmetic and shapes: maths for beginners, playful and clear.
6 appsOpen collectionWant to use these apps in your courses? Let’s find out what works for you.
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