get_probabilities {coalitions} R Documentation

## Wrapper for calculation of coalition probabilities from survey

### Description

Given a table with simulations in the rows and coalitions in the columns, this function returns the coalition probabilities for a specified coalition, by default excluding superior coalitions first

### Usage

get_probabilities(
x,
coalitions = list(c("cdu"), c("cdu", "fdp"), c("cdu", "fdp", "greens"), c("spd"),
c("spd", "left"), c("spd", "left", "greens")),
nsim = 1e+05,
distrib.fun = sls,
seats_majority = 300L,
seed = as.numeric(now()),
correction = NULL
)


### Arguments

 x A table containing one row per survey and survey information in long format in a separate column named survey. coalitions A list of coalitions for which coalition probabilities should be calculated. Each list entry must be a vector of party names. Those names need to correspond to the names in majority_df. nsim number of simulations distrib.fun Function to calculate seat distribution. Defaults to sls (Sainte-Lague/Schepers). seats_majority The number of seats needed to obtain majority. seed sets seed correction A positive number. If not NULL, each sample from the Dirichlet distribution will be additionally "corrected" by a random number from U(-1*correction, 1*correction). This can be used to introduce extra variation which might be useful due to rounding errors from reported survey results (or add an additional source of variation in general).

calculate_prob

### Examples

library(coalitions)
library(dplyr)
# get the latest survey for a sample of German federal election polls
surveys <- get_latest(surveys_sample)
# calculate probabilities for two coalitions
probs <- get_probabilities(surveys,
coalitions = list(c("cdu", "fdp"),
c("spd", "left", "greens")),
nsim = 100) # ensure fast runtime with only 100 simulations
probs %>% tidyr::unnest("probabilities")


[Package coalitions version 0.6.23 Index]