 laishidua/ ExpectedRiskValue / 0.1.4

This class defines the expected rate value based of a risk. We use the next formula:

E(R) = [(p(P))] - [(1-p)(L)]

The expectative consist of certain probabilities of win or loss and the amount of the factors
that you win or loss. If the rate of return if is > 0, We can win depending of the risk.

E(R) is calculated in term of each individual game.
p = probability of win.
1-p = probability of loss.
P = win factor.
L = loss factor.

Examples:
1.- I am going to flipping a coin, if the coin gets head I win \$10, else I loss \$10.
Will I take the risk?
E(R) = (0.5*10) - (1-0.5)(10) = 0
So I wont. because the rate of return is 0, there is no money!!
INPUT: [0.5, 1, 1]

2.- If I win I get \$2, else I loss \$1. I have 60% probability to loss and 40% of win.
E(R) = (0.4*2) - (1-0.4)(1) = 0.2
So the average rate of return is \$0.20 each game. Maybe I will.
INPUT: [0.4, 2, 1]

3.- I win \$2 if the thin wrestler win, else \$1 if fat wrestler win.
If thin wrestler has 30% probability to win.
Will I take the risk for this wrestling?
E(R) = (0.3*2) - (1-0.3)(1) = 0.6 - 0.7 = -0.1
So I wont. I loss -0.1 each game, so If I play 100 times -> 100-0.1=10. I could loss \$10
INPUT: [0.3, 2, 1]