Round-robin for football leagues

Description

Posterior predictive probabilities for a football season in a round-robin format

Usage

foot_round_robin(object, data, teams = NULL, output = "both")

Arguments

object	An object either of class stanFoot, CmdStanFit, stanfit.
data	A data frame containing match data with columns: periods: Time point of each observation (integer >= 1). home_team: Home team's name (character string). away_team: Away team's name (character string). home_goals: Goals scored by the home team (integer >= 0). away_goals: Goals scored by the away team (integer >= 0).
teams	An optional character vector specifying team names to include. If NULL, all teams are included.
output	An optional character string specifying the type of output to return. One of "both", "table", or "plot". Default is "both".

Details

For Bayesian models fitted via stan_foot the round-robin table is computed according to the simulation from the posterior predictive distribution of future (out-of-sample) matches. The dataset should refer to one or more seasons from a given national football league (Premier League, Serie A, La Liga, etc.).

Value

If output = "both" a list with:

• round_table: A data frame of matchups (Home, Away), observed scores, and Home_prob (median posterior probability of a home win).

• round_plot: A ggplot heatmap of home-win probabilities with observed scores overlaid.

If output = "table" or "plot", returns only that component.

Author(s)

Leonardo Egidi legidi@units.it and Roberto Macrì Demartino roberto.macridemartino@deams.units.it

Examples

## Not run: 
if (instantiate::stan_cmdstan_exists()) {
  library(dplyr)

  data("italy")
  italy_1999_2000 <- italy %>%
    dplyr::select(Season, home, visitor, hgoal, vgoal) %>%
    dplyr::filter(Season == "1999" | Season == "2000")

  colnames(italy_1999_2000) <- c("periods", "home_team", "away_team", "home_goals", "away_goals")

  fit <- stan_foot(italy_1999_2000, "double_pois", predict = 45, iter_sampling = 200)

  foot_round_robin(fit, italy_1999_2000)
  foot_round_robin(fit, italy_1999_2000, c("Parma AC", "AS Roma"))
}

## End(Not run)