Turning to your question, yes, white noise does have zero mean even if this is not explicitly stated because if the mean were nonzero, then the ... ... <看更多>

Your initial noise is uniformly distributed between -1 & +1. Your second noise is also uniformly disributed between -1 & +1, because mean is ... ... <看更多>

In time series analysis, a sequence of independent identically distributed (IID) Normal random variables with mean zero and variance σ2 is known ... ... <看更多>