Views on Copulas — view_on

Helper to construct constraints on copulas for entropy programming.

Usage

view_on_copula(x, simul, p)

# S3 method for default
view_on_copula(x, simul, p)

# S3 method for matrix
view_on_copula(x, simul, p)

# S3 method for xts
view_on_copula(x, simul, p)

# S3 method for tbl_df
view_on_copula(x, simul, p)

Arguments

x: A multivariate copula.
simul: A simulated target copula.
p: An object of the ffp class.

Value

A list of the view class.

Examples

# \donttest{
  set.seed(1)
  library(ggplot2)

  # Invariants
  ret <- diff(log(EuStockMarkets))
  u <- apply(ret, 2, stats::pnorm) # assuming normal copula
  n <- nrow(u)

  #' Prior probability distribution
  prior <- rep(1 / n, n)

  # Simulated marginals
  simul_marg <- bootstrap_scenarios(ret, as_ffp(prior), as.double(n))

  # Copulas derived from the simulated margins
  simul_cop <- apply(simul_marg, 2, stats::pnorm) # assuming normal copula

  views <- view_on_copula(x = u, simul = simul_cop, p = prior)
  views
#> # ffp view
#> Type:  View On Copula
#> Aeq :  Dim 34 x 1859 
#> beq :  Dim 34 x 1 

  ep <- entropy_pooling(p = prior, Aeq = views$Aeq, beq = views$beq, solver = "nloptr")
  autoplot(ep)

# }