I want to calculate the Mean absolute percentage error (MAPE) for my copula model. I am stuck at the forecasting step. I am not specifying the copula here for different data pairs.
1. I have two time series $X$ and $Y$. I found best GARCH parameters $\alpha$ and $\beta$ assuming 0 mean.
2. The Kendals $\tau$ between two variables is $\tau$
3. Then I found best copula and had its parameters say $\kappa$ and $\omega$.
4. Now for forecasting I need to generate residuals using my copula parameters found in step 3.
How to do this if I want to enter the copula parameters MANUALLY and not use some $param=fit$ type of code in R.
I can work in R as well as excel. Please if somebody could help me with the exact steps of point 4.