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rmgarch (version 1.2-9)

cgarchsim-methods: function: Copula-GARCH Simulation

Description

Method for creating a Copula-GARCH simulation object.

Usage

cgarchsim(fit, n.sim = 1000, n.start = 0, m.sim = 1, 
startMethod = c("unconditional", "sample"), presigma = NULL, preresiduals = NULL, 
prereturns = NULL, preR = NULL, preQ = NULL, preZ = NULL, rseed = NULL, 
mexsimdata = NULL, vexsimdata = NULL, cluster = NULL, only.density = FALSE, 
prerealized = NULL, ...)

Arguments

fit
A cGARCHfit object created by calling cgarchfit.
n.sim
The simulation horizon.
n.start
The burn-in sample.
m.sim
The number of simulations.
startMethod
Starting values for the simulation. Valid methods are unconditional for the expected values given the density, and sample for the ending values of the actual data from the fit object. This is mostly related to th
presigma
Allows the starting sigma values to be provided by the user for the univariate GARCH dynamics.
prereturns
Allows the starting return data to be provided by the user for the conditional mean simulation.
preresiduals
Allows the starting residuals to be provided by the user and used in the GARCH dynamics simulation.
preR
Allows the starting correlation to be provided by the user and mostly useful for the static copula.
preQ
Allows the starting DCC-Q value to be provided by the user and though unnecessary for the first 1-ahead simulation using the sample option in the startMethod, this is key to obtaining a rolling n-ahea
preZ
Allows the starting transformed standardized residuals (used in the DCC model) to be provided by the user and though unnecessary for the first 1-ahead simulation using the sample option in the startMethod, this is key
rseed
Optional seeding value(s) for the random number generator. This should be of length equal to m.sim.
mexsimdata
A list (equal to the number of asset) of matrices of simulated external regressor-in-mean data with row length equal to n.sim + n.start. If the fit object contains external regressors in the mean equation, this must be provided else will be assum
vexsimdata
A list (equal to the number of asset) of matrices of simulated external regressor-in-variance data with row length equal to n.sim + n.start. If the fit object contains external regressors in the variance equation, this must be provided else will
cluster
A cluster object created by calling makeCluster from the parallel package. If it is not NULL, then this will be used for parallel estimation (remember to stop the cluster on completion).
only.density
Whether to return only the simulated returns (discrete time approximation to the multivariate density). This is sometimes useful in order to control memory management for large simulations not requiring any other information.
prerealized
Allows the starting realized volatility values to be provided by the user for the univariate GARCH dynamics.
...
.

Value

  • A cGARCHsim object containing details of the Copula-GARCH simulation.

Details

Since there is no explicit forecasting routine, the user should use this method for incrementally building up n-ahead forecasts by simulating 1-ahead, obtaining the means of the returns, sigma, Rho etc and feeding them to the next round of simulation as starting values. The rmgarch.tests folder contains specific examples which illustrate this particular point.

References

Joe, H. Multivariate Models and Dependence Concepts, 1997, Chapman & Hall, London. Genest, C., Ghoudi, K. and Rivest, L. A semiparametric estimation procedure of dependence parameters in multivariate families of distributions, 1995, Biometrika, 82, 543-552.