Simulates a GARCH process which is an example of a weak white noise.
Usage
simGARCH(n, c, A, B = NULL, ninit = 100)
Arguments
n
Number of observations.
c
Positive number.
A
Vector of ARCH coefficients >=0.
B
Vector of GARCH coefficients >=0. If NULL, the
simulation is a ARCH process.
ninit
Length of 'burn-in' period.
Value
Vector of size n containing a nonlinear sequence \(\epsilon_t\) such as
$$\epsilon_{t} = H_{t}^{1 / 2} \eta_{t}$$ where $$H_{t} = c +
a_{1}\epsilon_{t - 1}^ {2}+...+a_{q}\epsilon_{t - q} ^{2} + b_{1}H_{t-1}+...+ b_{p}H_{t-p}$$
References
Francq C. and Zako<U+00EF>an J.M., 2010, GARCH models: structure, statistical inference and financial applications