uniform function

Uniform distribution

Uniform distribution

Computes the pdf, cdf, value at risk and expected shortfall for the uniform distribution given by [REMOVE_ME]\displaystylef(x)=1ba,\displaystyleF(x)=xaba,VaRp(X)=a+p(ba),ESp(X)=a+p2(ba)[REMOVEME2] \begin{array}{ll}&\displaystylef (x) = \frac {1}{b - a},\\&\displaystyleF (x) = \frac {x - a}{b - a},\\&\displaystyle{\rm VaR}_p (X) = a + p (b - a),\\&\displaystyle{\rm ES}_p (X) = a + \frac {p}{2} (b - a)\end{array} [REMOVE_ME_2]

for a<x<ba < x < b, 0<p<10 < p < 1, <a<-\infty < a < \infty , the first location parameter, and <a<b<-\infty < a < b < \infty , the second location parameter.

Description

Computes the pdf, cdf, value at risk and expected shortfall for the uniform distribution given by

\displaystylef(x)=1ba,\displaystyleF(x)=xaba,VaRp(X)=a+p(ba),ESp(X)=a+p2(ba) \begin{array}{ll}&\displaystylef (x) = \frac {1}{b - a},\\&\displaystyleF (x) = \frac {x - a}{b - a},\\&\displaystyle{\rm VaR}_p (X) = a + p (b - a),\\&\displaystyle{\rm ES}_p (X) = a + \frac {p}{2} (b - a)\end{array}

for a<x<ba < x < b, 0<p<10 < p < 1, <a<-\infty < a < \infty , the first location parameter, and <a<b<-\infty < a < b < \infty , the second location parameter.

duniform(x, a=0, b=1, log=FALSE) puniform(x, a=0, b=1, log.p=FALSE, lower.tail=TRUE) varuniform(p, a=0, b=1, log.p=FALSE, lower.tail=TRUE) esuniform(p, a=0, b=1)

Arguments

  • x: scaler or vector of values at which the pdf or cdf needs to be computed
  • p: scaler or vector of values at which the value at risk or expected shortfall needs to be computed
  • a: the value of the first location parameter, can take any real value, the default is zero
  • b: the value of the second location parameter, can take any real value but must be greater than a, the default is 1
  • log: if TRUE then log(pdf) are returned
  • log.p: if TRUE then log(cdf) are returned and quantiles are computed for exp(p)
  • lower.tail: if FALSE then 1-cdf are returned and quantiles are computed for 1-p

Returns

An object of the same length as x, giving the pdf or cdf values computed at x or an object of the same length as p, giving the values at risk or expected shortfall computed at p.

References

Stephen Chan, Saralees Nadarajah & Emmanuel Afuecheta (2016). An R Package for Value at Risk and Expected Shortfall, Communications in Statistics - Simulation and Computation, 45:9, 3416-3434, tools:::Rd_expr_doi("10.1080/03610918.2014.944658")

Author(s)

Saralees Nadarajah

Examples

x=runif(10,min=0,max=1) duniform(x) puniform(x) varuniform(x) esuniform(x)
  • Maintainer: Leo Belzile
  • License: GPL (>= 2)
  • Last published: 2023-04-22

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