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evd (version 1.0-0)

bvalog: The Bivariate Asymmetric Logistic Distribution

Description

Density, distribution function and random generation for the bivariate asymmetric logistic distribution.

Usage

dbvalog(x, dep, asy, mar1 = c(0, 1, 0), mar2 = mar1, log = FALSE) 
pbvalog(q, dep, asy, mar1 = c(0, 1, 0), mar2 = mar1) 
rbvalog(n, dep, asy, mar1 = c(0, 1, 0), mar2 = mar1)

Arguments

x, q
a vector of length two or a matrix with two columns, in which case the density/distribution is evaluated across the rows.
n
number of observations.
dep
dependence parameter.
asy
a vector containing the two asymmetry parameters.
mar1, mar2
vectors of length three containing marginal parameters.
log
logical; if TRUE, the log density is returned.

Value

  • dbvalog gives the density, pbvalog gives the distribution function and rbvalog generates random deviates.

Details

The bivariate asymmetric logistic distribution function with parameters $\code{dep} = r$ and $\code{asy} = (t_1,t_2)$ is $$G(z_1,z_2) = \exp\left{-(1-t_1)y_1-(1-t_2)y_2- [(t_1y_1)^{1/r}+(t_2y_2)^{1/r}]^r\right}$$ where $0 < r \leq 1$, $0 \leq t_1,t_2 \leq 1$, and $$y_i = {1+s_i(z_i-a_i)/b_i}^{-1/s_i}$$ for $1+s_i(z_i-a_i)/b_i > 0$ and $i = 1,2$, where the marginal parameters are given by $\code{mari} = (a_i,b_i,s_i)$, $b_i > 0$. If $s_i = 0$ then $y_i$ is defined by continuity. The univariate marginal distributions are generalized extreme value.

References

Stephenson, A. G. (2002) Simulating multivariate extreme value distributions of logistic type. To be published - available on request.

See Also

abvlog, rbvlog, rgev, rmvalog

Examples

Run this code
dbvalog(matrix(rep(0:4,2),ncol=2), .7, c(0.5,1))
pbvalog(matrix(rep(0:4,2),ncol=2), .7, c(0.5,1))  
rbvalog(10, .7, c(0.5,1))

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