The Uniform distribution

Source: R/dist_uniform.R

[Stable]

A distribution with constant density on an interval.

dist_uniform(min, max)

Arguments

min, max

lower and upper limits of the distribution. Must be finite.

Details

We recommend reading this documentation on https://pkg.mitchelloharawild.com/distributional/, where the math will render nicely.

In the following, let \(X\) be a Poisson random variable with parameter lambda = \(\lambda\).

Support: \([a,b]\)

Mean: \(\frac{1}{2}(a+b)\)

Variance: \(\frac{1}{12}(b-a)^2\)

Probability mass function (p.m.f):

$$ f(x) = \frac{1}{b-a} for x \in [a,b] $$ $$ f(x) = 0 otherwise $$

Cumulative distribution function (c.d.f):

$$ F(x) = 0 for x < a $$ $$ F(x) = \frac{x - a}{b-a} for x \in [a,b] $$ $$ F(x) = 1 for x > b $$

Moment generating function (m.g.f):

$$ E(e^{tX}) = \frac{e^{tb} - e^{ta}}{t(b-a)} for t \neq 0 $$ $$ E(e^{tX}) = 1 for t = 0 $$

See also

stats::Uniform

Examples

dist <- dist_uniform(min = c(3, -2), max = c(5, 4))

dist
#> <distribution[2]>
#> [1] U(3, 5)  U(-2, 4)
mean(dist)
#> [1] 4 1
variance(dist)
#> [1] 0.3333333 3.0000000
skewness(dist)
#> [1] 0 0
kurtosis(dist)
#> [1] -1.2 -1.2

generate(dist, 10)
#> [[1]]
#>  [1] 3.853052 3.101802 3.011493 3.763697 4.989991 3.282418 3.707240 4.007333
#>  [9] 3.946254 4.329282
#> 
#> [[2]]
#>  [1]  1.4899095  3.7600330  1.3168641  3.9419258  0.6191111  0.8674027
#>  [7] -0.4445284 -1.3764096 -0.4060009 -1.8360372
#> 

density(dist, 2)
#> [1] 0.0000000 0.1666667
density(dist, 2, log = TRUE)
#> [1]      -Inf -1.791759

cdf(dist, 4)
#> [1] 0.5 1.0

quantile(dist, 0.7)
#> [1] 4.4 2.2