Simulates parameters for either a regression formula or a time series model specified by a numeric vector.
A numeric vector of parameters, of the appropriate length as determined by the argument fmla.
This function simply simulates whatever number of parameters is required of the model. In the case of regression, this means one parameter for each variable in the RHS of the formula, while for a time series, it means one parameter for each component in the AR, MA, SAR, and SMA parts of the model.