Supported distributions
The binomial distribution models the number of successes in n independent trials, each with probability p. Its PMF gives P(X = k) = C(n,k) × p^k × (1−p)^(n−k).
The Poisson distribution models the number of events in a fixed interval given an average rate λ. Its PMF is P(X = k) = e^(−λ) × λ^k / k!.
The normal (Gaussian) distribution is the continuous bell curve defined by mean μ and standard deviation σ. The calculator computes the PDF value and the CDF using a numerical approximation of the error function.
The continuous uniform distribution assigns equal probability density to all values in the interval [a, b].
Binomial: P(X=k) = C(n,k) × p^k × (1−p)^(n−k)
Probability of exactly k successes in n trials.
Poisson: P(X=k) = e^(−λ) × λ^k / k!
Probability of exactly k events given average rate λ.
Normal CDF: Φ(x) = ½[1 + erf((x−μ) / (σ√2))]
Cumulative probability up to x for a normal distribution.