birthday simulation

library(tidyverse)

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library(plotly)

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n = 70
p = numeric(n)

for (i in 1:n){
  prob_match = 1 - (0:(i-1))/366
  p[i] = 1 - prod(prob_match)
}

graph = ggplot(data.frame(x = 1:n, probability = p), aes(x=x, y=probability)) +
  geom_point() +
  xlab("Number of people") + ylab("Probability of at least one match")
ggplotly(graph)