rsCIR {sde}

Cox-Ingersoll-Ross process stationary law

Description

Density, distribution function, quantile function, and random generation of the stationary law for the Cox-Ingersoll-Ross process.

Usage

dsCIR(x, theta, log = FALSE)
psCIR(x, theta, lower.tail = TRUE, log.p = FALSE) 
qsCIR(p, theta, lower.tail = TRUE, log.p = FALSE)
rsCIR(n=1, theta)

Arguments

x

vector of quantiles.

p

vector of probabilities.

theta

parameter of the Cox-Ingersoll-Ross process; see details.

n

number of random numbers to generate from the conditional distribution.

log, log.p

logical; if TRUE, probabilities p are given as \log(p).

lower.tail

logical; if TRUE (default), probabilities are P[X <= x]; otherwise P[X > x].

Details

This function returns quantities related to the stationary law of the process solution of

{\rm d}X_t = (\theta_1 - \theta_2 X_t){\rm d}t + \theta_3\sqrt{X_t} {\rm d}W_t.

Constraints: 2\theta_1 > \theta_3^2, all \theta positive.

Value

x

a numeric vector

Author(s)

Stefano Maria Iacus

References

Cox, J.C., Ingersoll, J.E., Ross, S.A. (1985) A theory of the term structure of interest rates, Econometrica, 53, 385-408.

See Also

rsCIR

Examples

rsCIR(n=1, theta=c(6,2,1))