plot_beta_binomial function

Plot a Beta-Binomial Bayesian Model

Consider a Beta-Binomial Bayesian model for parameter $\pi$ with a Beta(alpha, beta) prior on $\pi$ and Binomial likelihood with n trials and y successes. Given information on the prior (alpha and data) and data (y and n), this function produces a plot of any combination of the corresponding prior pdf, scaled likelihood function, and posterior pdf. All three are included by default.

plot_beta_binomial(
  alpha,
  beta,
  y = NULL,
  n = NULL,
  prior = TRUE,
  likelihood = TRUE,
  posterior = TRUE
)

Arguments

• alpha, beta: positive shape parameters of the prior Beta model
• y: observed number of successes
• n: observed number of trials
• prior: a logical value indicating whether the prior model should be plotted
• likelihood: a logical value indicating whether the scaled likelihood should be plotted
• posterior: a logical value indicating whether posterior model should be plotted

Returns

a ggplot

Examples

plot_beta_binomial(alpha = 1, beta = 13, y = 25, n = 50)
plot_beta_binomial(alpha = 1, beta = 13, y = 25, n = 50, posterior = FALSE)