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The Binomial Distribution

Syntax

dbinom(x, n, p)
pbinom(x, n, p)
qbinom(prob, n, p)
rbinom(nobs, n, p)

Arguments

x vector of quantiles.
prob vector of probabilities.
nobs number of observations to generate.
n number of trials.
p probability of success on each trial.

Value

These functions provide information about the binomial distribution with parameters n and p. dbinom gives the density, pbinom gives the distribution function qbinom gives the quantile function and rbinom generates random deviates.

The binomial distribution has density

p(x) = Choose(n,x) p^x (1-p)^(n-x)

((Equations will(?) come with HTML 3.x ))
for x = 0, ..., n.

Examples

# Compute P(45 < X < 55) for X Binomial(100,0.5) sum(dbinom(46:54, 100, 0.5))