shapes of uncertainty
Distributions.
The shapes uncertainty likes to take — bell, skew, spike, heavy tail.
23 live pieces
· 6
more on the way
Normal distribution
Tune μ and σ; watch the bell shift and stretch against samples drawn live.
Poisson distribution
Count rare events with λ — and watch the bars converge to a Normal as λ grows.
Binomial distribution
n coins, probability p — see the discrete count distribution shift and stretch toward Gaussian.
Exponential distribution
Waiting times between Poisson events — and the only continuous memoryless distribution.
Beta distribution
A distribution over probabilities. The Bayesian conjugate prior for coin flips.
Cauchy distribution
Looks like a Normal but has no mean — the running average never settles.
Geometric distribution
Count flips until the first head. The only discrete memoryless distribution.
Log-normal distribution
Multiply independent shocks and the product goes log-normal. Income, wealth, viral spreads.
Uniform distribution
Every value equally likely — the flattest distribution. Yet sums of uniforms still go Gaussian.
Gamma distribution
Waiting time for k Poisson events. Shape k controls skew; rate λ controls scale.
Bernoulli distribution
One flip, two outcomes. The atom every other discrete distribution is built from.
Negative binomial
Flip until the r-th success. Dispersion that Poisson can’t match.
Hypergeometric distribution
Sampling without replacement. Binomial in the limit as the population grows.
Student's t distribution
Heavier tails than Normal at small ν. Shrinks to a Gaussian as degrees of freedom grow.
Chi-squared distribution
Sum of k squared standard normals. The engine of variance tests.
F distribution
Ratio of two chi-squareds. The ANOVA distribution.
Weibull distribution
Failure times. Shape k flips the hazard rate from falling to rising.
Pareto distribution
Power-law tails. The 80/20 rule lived on a log-log axis.
Laplace distribution
Two exponentials back-to-back. The prior behind L1 regularization.
Logistic distribution
The CDF everyone secretly uses. Lighter centre, heavier tails than Normal.
Gumbel distribution
The distribution of maxima. Extreme-value theory in one curve.
Triangular distribution
Min, mode, max — a cheap stand-in when that is all you know.
Von Mises distribution
soon Normal wrapped around a circle. Wind directions, clock arithmetic.
Dirichlet distribution
soon Distribution over the simplex. Conjugate prior for the categorical.
Multivariate Normal
soon Drag the correlation and watch the ellipse rotate. A 2D slice of the Gaussian.
Gaussian mixture
Two bells, one weight. Unmixes into components you can steer by hand.
Stable distributions
soon The α-stable family. Normal and Cauchy are the endpoints; everything between is heavy-tailed.
Zipf distribution
soon Rank-frequency power law. Word counts, city sizes, log-log straight lines.
Empirical CDF
soon A staircase over samples. Converges uniformly to the true CDF — that’s Glivenko-Cantelli.