which parameter is the return on curve does the garch approach model prices or returns? what is the gardch model what does the gardh approach model prices or returns what would be the return of the gard model what model approaches returns what's the model at $t$ what is the value of the time series at time $t$ how to do the curve for a time series what is the return at time $t$ in the agarch model what is the y_t how do you calculate the sigma_t return what is the model of the curve of the garch what is the maximum log-likelihood of the curve why does the curve approach model price or return? what is the model value for a curve in a cash flow curve what is gard model price what is the model used to calculate a return how would model gach approach return when a value is a price, a return is a price