rPRDTS {SubTS}R Documentation

Simulation from p-RDTS distributions.

Description

Simulates from p-rapidly decreasing tempered stable (p-RDTS) distributions.

Usage

rPRDTS(n, t, mu, alpha, p, step = 1)

Arguments

n

Number of observations.

t

Parameter >0.

mu

Parameter >0.

alpha

Parameter in (-infty,1)

p

Parameter >1 if 0<=alpha<1, >0 if alpha<0.

step

Tuning parameter. The larger the step, the slower the rejection sampling, but the fewer the number of terms. See Hoefert (2011) or Section 4 in Grabchak (2019).

Details

Simulates from a p-RDTS distribution. When alpha >=0, uses Theorem 1 in Grabchak (2021) and when alpha<0 uses the method in Section 4 of Grabchak (2021). This distribution has Laplace transform

L(z) = exp( t int_0^infty (e^(-xz)-1)e^(-(mu*x)^p) x^(-1-alpha) dx ), z>0

and Levy measure

M(dx) = t e^(-(mu*x)^p) x^(-1-alpha) 1(x>0)dx.

Value

Returns a vector of n random numbers.

Author(s)

Michael Grabchak and Lijuan Cao

References

M. Grabchak (2019). Rejection sampling for tempered Levy processes. Statistics and Computing, 29(3):549-558

M. Grabchak (2021). An exact method for simulating rapidly decreasing tempered stable distributions. Statistics and Probability Letters, 170: Article 109015.

M. Hofert (2011). Sampling exponentially tilted stable distributions. ACM Transactions on Modeling and Computer Simulation, 22(1), 3.

Examples

rPRDTS(20, 2, 1, .7, 2)
rPRDTS(20, 2, 1, 0, 2)
rPRDTS(20, 2, 1, -.7, 2)

[Package SubTS version 1.0 Index]