[R] VCOV Source Code

Dear R Help, I wonder the way to show the source code of [vcov] command. Usually, it can show the source code after input the command and enter. But for [vcov], it shows function (object, ...) UseMethod("vcov") I appreciate for your help. Best wishes. Christina [[al

[R] Cointegration and ECM in Package {urca}

Dear R Core Team, I am using package {urca} to do cointegration and estimate ECM model, but I have the following two problems: (1)I use ca.jo() to do cointegration first and can get the cointegration rank, alpha and beta. The next step is to test some restrictions on beta with blrtest(

[R] How to return individual equation from {aidsEst} in package [micEcon]?

Hi, R core team I am using the function {aidsEst} in package [micEcon] to do an AIDS model now. So far, everything is good. But I want to test the auto correlation and heteroskedasticity of the individual equation from AIDS demand system. How can I return the individual equation? PS: ser