Lots of maths involved here. Atleast I now know we can study and predict the bitcoin prices to some extent. I've been following Metcalfe's Law which I do believe still holds. The prices are determined with the basic economics.. scarcity, utility, supply and demand which fall in line with Metcalfe's Law;
the value, in this case market capitalization (cap) of a network is proportional to the number of users squared
Coins getting scarce in the market come as a result of higher number of users.. This increases the demand which increases the value of the coins hence increasing the prices. And the viceverser leads to the fall of the prices.