Texas Hold'em

Probability Puzzles in R

Peter Chi

Assistant Professor of Statistics Villanova University

Community Cards in Texas Hold'em

Outs: Cards that improve hand from losing to winning

Complement Rule: $P(A) = 1 - P(A^c)$

p_lose <- choose(10-3,2) / choose(10,2)
p_win <- 1 - p_lose
p_win

0.5333333

Using choose on a vector:

outs <- c(0,1,2,3)

p_lose <- choose(10-outs,2) / choose(10,2)
p_win <- 1 - p_lose
p_win

0.0000000 0.2000000 0.3777778 0.5333333

$$ E(X) = \sum_{\text{all values}} x \cdot P(X=x) $$

Coin flip wager:

probs <- c(0.5, 0.5)
values <- c(-2, 3)
probs * values

-1  1.5

sum(probs * values)

0.5

Probability Puzzles in R