I actually do not trust this "predictor" site to give out correlations without knowing the algorithm behind it. Do you have any idea what algorithm they might be using? Unless I know that I wont use it. Also if I know that then I would probably learn how to apply it myself. 
Get my point? You cant always use these methods to mitigate risks. The best way to mitigate the risk is invest in those altcoins that you know (not feel) have a reason to go up in price and demand. Sadly 99% of altcoins dont have any method to generate a market demand and thus they die out.
To be completely honest, I do not prefer to go for the altcoins at all. Keeping the focus on bitcoin and using a dollar cost averaging on bitcoin to buy and sell at proper low and high respectively is what I feel minimizes risks.
Get my point? You cant always use these methods to mitigate risks. The best way to mitigate the risk is invest in those altcoins that you know (not feel) have a reason to go up in price and demand. Sadly 99% of altcoins dont have any method to generate a market demand and thus they die out.
To be completely honest, I do not prefer to go for the altcoins at all. Keeping the focus on bitcoin and using a dollar cost averaging on bitcoin to buy and sell at proper low and high respectively is what I feel minimizes risks.