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. 
I think it's related to psychology, since Bitcoin is the pioneer of all cryptocurrency, and that is embedded in people's mind, makes them think that Bitcoin is the mother of all cryptocurrency, that way when ever the price of BTC dropping it affect people to sell their altcoin due to worry if their coins will loss its value, that way makes the price of altcoins dropping.