I've been monitoring the market for a couple of months now. Most of the coin value rely on the price of Bitcoin. If the BTC price goes up, every altcoins will follow and if it will goes down, the price of every altcoins will goes down as well. But the question is, Bitcoin price/value is still going up but the price/value of every altcoins especially Ethereum goes down. How did this happen? Any logical or scientific basis to explain this. As of now, I am still confuse. 
It could not be used as a reference. bitcoin rise even when instantaneous time altcoin thus far down instead. otherwise when bitcoin down often also altcoin all down. It is indeed confusing and would not be known to the certainty. There is no official reference when bitcoin ride then all altcoin will also rise.