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EARLY ACCESS JMaths is in active development — new content added regularly

Interactive Apps

50 interactive tools for exploring mathematical concepts

Statistics & Probability

Normal Distribution
Explore the bell curve with adjustable mean and standard deviation. Shade probability regions.
Binomial Distribution
Visualise binomial probabilities with adjustable n and p. Compare to normal approximation.
Regression Explorer
Fit linear, quadratic and other regression models to data. See residuals and r-squared.
Population Parameters Walkthrough
Understand the difference between population parameters and sample statistics.
Sampling Variability Walkthrough
See how sample statistics vary from sample to sample through repeated sampling.
Bessel's Correction Walkthrough
Discover why we divide by n-1 for sample variance through interactive simulation.
Central Limit Theorem Walkthrough
Watch the sampling distribution of the mean become normal regardless of population shape.
Confidence Interval Walkthrough
Build intuition for confidence intervals by generating many intervals and checking coverage.
Bayes' Theorem Walkthrough
Step through conditional probability problems using tree diagrams and Bayes' theorem.
Probability Rules Walkthrough
Interactive guide to addition and multiplication rules with visual probability models.
Venn Diagram Walkthrough
Solve probability problems using interactive Venn diagrams with two and three events.
Chi-Squared Walkthrough
Perform chi-squared goodness-of-fit and independence tests step by step.
Type I and Type II Errors
Visualise the relationship between significance level, power, and Type I/II errors.
Binomial Type II Error
Explore Type II error probability in binomial hypothesis tests with adjustable parameters.
Capture-Recapture Simulation
Estimate a hidden population by marking, releasing and recapturing animals. Compare Lincoln-Petersen and Chapman estimators with Monte Carlo trials.
Capture-Recapture Walkthrough
Step-by-step explanation of the capture-recapture method: mark, release, recapture, the proportion equation, and why running many trials converges on the truth.
Box Plot Explorer
Compare age distributions across groups with vertical or horizontal box plots. Toggle groups to see the scale adapt.