I am using the function McLeod.Li.test in the TSA package. According to the help file in R, this function “Performs the McLeod-Li test for conditional heteroscedasticity (ARCH).”
However, it has been mentioned on page 50 of the book “Introduction to Time Series and Forecasting, Brockwell and Davis, 2nd edition” that the McLeod-Li test “can be used as a further test for the iid hypothesis”.
Question: Is it true to say that the McLeod-Li test can be used to check the “conditional heteroscedasticity” as well as the “iid assumption”? If not, which one is the correct null hypothesis?