Statistical Simulations

Drag a point and watch the mean chase it while the median stays put

Explore the surprising probability of shared birthdays in a group

Visualize how sample means converge to the true population mean

Estimate r from a scatter plot, then see how close you got across ten rounds

Visualize bootstrap resampling to estimate sampling distributions and construct confidence intervals without assumptions

See how sample means follow a normal distribution regardless of the population distribution

Understand how confidence intervals capture the true population parameter

See how sample statistics vary across repeated samples with a three-panel population, sample, and sampling distribution view

Drag a point across a scatter plot and watch the regression line pivot

Four datasets with identical statistics that look nothing alike, plus the Datasaurus Dozen

See why you shouldn’t peek at a running A/B test — watch the false-positive rate climb as optional stopping gives chance more shots at fooling you

Visualize Type I/II errors, statistical power, and p-value distributions by running hundreds of hypothesis tests

Build your own p-hack — see how extra outcomes, optional stopping, outlier exclusions, and subgroup fishing turn studies of nothing into "significant" findings

Use random sampling to solve complex probability problems

Visualize the meaning and interpretation of p-values