As much i know predicting a bull / bear run can not be done , who ever is predicting is just a guess work and if it goes correct it is good , if you always trade in practical way then ithink even in 2019 we will bear trend for some months.
I guess you are forgetting completely about technical analysis which involves lot of trading tools and strategies. Yes, you can predict the direction of market using technical tools even if you are unable to predict the exact price levels. But, OP here is stating about predicting an upcoming movement in small exchanges based on bitstamp and other major exchanges. It may be possible in some occasions and cannot be sure it will work for all 100% of times. Just like any other strategies.
Predicting the direction of a market is involved lots of criteria and factors. When everything will be meeting and satisfied then there will be chances for accurate predictions. But we cannot be sure that each and every parameter will be met all the times so that we can be sure about accurate prediction.