Suppose you bought a stock at $100. You have placed a  limit order to sell the stock if it reaches $150. This is called  the profit taking price. Now you want to limit your  downside and need a stop loss order. Assume that stock  moves up or down by $1. In the traders view a bull market  scenario occurs with the probability of an up move of p =  0.55 and that of a down move of q = 0.45. Also, in the
traders view a bear market scenario occurs with the  probability of an up move of p = 0.45 and that of a down  move of q = 0.55. 

What is the best stop loss to set? Use  the Gamblers Ruin methodology.

Now suppose that bull market (and hence the bear  market) probabilities change to p= 0.60 and q = 0.4. 

How  does the stop loss change?