Exercise 3. American Roulette expected value
In American roulette, the payout for winning on green is $17. This means that if you bet $1 and it lands on green, you get $17 as a prize.In the previous exercise, you created a model to predict your winnings from betting on green.
Now, compute the expected value of \(X\), the random variable you generated previously.
This exercise is part of the course
HarvardX Data Science - Probability (PH125.3x)
Exercise instructions
- Using the chances of winning $17 (
p_green) and the chances of losing $1 (p_not_green), calculate the expected outcome of a bet that the ball will land in a green pocket.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# The variables 'green', 'black', and 'red' contain the number of pockets for each color
green <- 2
black <- 18
red <- 18
# Assign a variable `p_green` as the probability of the ball landing in a green pocket
p_green <- green / (green+black+red)
# Assign a variable `p_not_green` as the probability of the ball not landing in a green pocket
p_not_green <- 1-p_green
# Calculate the expected outcome if you win $17 if the ball lands on green and you lose $1 if the ball doesn't land on green