Coalitions

Projects the seats of coalitions and the probability that they reach a majority, based on the simulations described in popSeats().

Usage

popCoalitions(
  x,
  seats,
  coalitions = NULL,
  threshold = 0,
  method = c("dhondt", "sainte-lague", "hare"),
  simulations = 2000,
  majority = NULL,
  level = 0.9,
  size = 3,
  trend = NULL,
  date = NULL
)

Arguments

x

A popPolls object, whose shares are taken from a trend (see popLatest()), or a named numeric vector of vote shares.

seats

Number of seats to distribute.

coalitions

List of coalitions, each a character vector of party codes, e.g. list(c("OEVP", "SPOE", "NEOS"), c("FPOE", "OEVP")). The names of the list are used as names of the coalitions.

threshold

Minimum share a party needs to get seats.

method

"dhondt", "sainte-lague" or "hare".

simulations

Number of simulations, 0 for none. Needs a trend with a variance, such as kalman.

majority

Seats needed for a majority, by default more than half.

level

Coverage of the seat range given by lower and upper.

size

Largest number of parties in a coalition if coalitions is not given.

trend

Name of the trend in x$trends, defaults to the one added last.

date

Date of the projection, defaults to the last date of the trend.

Value

A data.table with the columns coalition, parties (the party codes, separated by +), seats (projected from the trend values), lower, upper (the range of seats) and pMajority (the share of simulations in which the coalition reaches a majority).

Details

Without coalitions, every combination of up to size parties is considered that reaches a majority in at least 1 % of the simulations, unless it contains a smaller combination that has a majority in at least half of them.

Examples

if (FALSE) { # \dontrun{
at = popRead('AT-parliament')
at = popAddTrend(at, name = 'kalman', type = 'kalman', args = list(smoothing = TRUE))
set.seed(1)
popCoalitions(at, seats = 183, threshold = 0.04)
popCoalitions(at, seats = 183, threshold = 0.04,
              coalitions = list(Zuckerl = c('OEVP', 'SPOE', 'NEOS'),
                                'Blau-Schwarz' = c('FPOE', 'OEVP')))
} # }