Question 1

What does this Binomial Distribution calculator compute?

Accepted Answer

It computes the Binomial PMF P(X=k), the CDF P(X≤k), the quantile for a given q, and shows mean/variance with a PMF bar plot.

Question 2

What do n, p, k and q mean?

Accepted Answer

n = number of independent trials, p = success probability per trial, k = number of successes, q = probability for the quantile (0–1).

Question 3

PMF vs CDF — what’s the difference?

Accepted Answer

PMF is the probability of exactly k successes. CDF is the probability of at most k successes (up to and including k).

Question 4

How is the quantile computed?

Accepted Answer

It returns the smallest integer k such that CDF(n,p,k) ≥ q.

Question 5

What are the mean and variance?

Accepted Answer

For X~Bin(n,p): mean = n·p and variance = n·p·(1−p).

Question 6

Is anything uploaded?

Accepted Answer

No. All calculations run locally in your browser.

Binomial Distribution Calculator

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