Extract weights from draws objects, with one weight per draw.
See weight_draws for details how to add weights to draws objects.
# S3 method for draws
weights(object, log = FALSE, normalize = TRUE, ...)(draws) A draws object.
(logical) Should the weights be returned on the log scale?
Defaults to FALSE.
(logical) Should the weights be normalized to sum to 1 on
the standard scale? Defaults to TRUE.
Arguments passed to individual methods (if applicable).
A vector of weights, with one weight per draw.
x <- example_draws()
# sample some random weights for illustration
wts <- rexp(ndraws(x))
head(wts)
#> [1] 0.44924386 0.01132425 0.79627288 0.06250828 0.26065786 0.04660613
# add weights
x <- weight_draws(x, weights = wts)
# extract weights
head(weights(x)) # defaults to normalized weights
#> [1] 1.191764e-03 3.004123e-05 2.112371e-03 1.658234e-04 6.914792e-04
#> [6] 1.236378e-04
head(weights(x, normalize=FALSE)) # recover original weights
#> [1] 0.44924386 0.01132425 0.79627288 0.06250828 0.26065786 0.04660613
head(weights(x, log=TRUE)) # get normalized log-weights
#> [1] -6.732320 -10.412940 -6.159944 -8.704587 -7.276678 -8.998154
# add weights which are already on the log scale
log_wts <- log(wts)
head(log_wts)
#> [1] -0.8001894 -4.4808090 -0.2278133 -2.7724563 -1.3445466 -3.0660231
x <- weight_draws(x, weights = log_wts, log = TRUE)
# extract weights
head(weights(x))
#> [1] 1.191764e-03 3.004123e-05 2.112371e-03 1.658234e-04 6.914792e-04
#> [6] 1.236378e-04
head(weights(x, log=TRUE, normalize = FALSE)) # recover original log_wts
#> [1] -0.8001894 -4.4808090 -0.2278133 -2.7724563 -1.3445466 -3.0660231
# add weights on log scale and Pareto smooth them
x <- weight_draws(x, weights = log_wts, log = TRUE, pareto_smooth = TRUE)
#> Pareto k-hat = 0.08.