Point Estimates and Credible Intervals for Selected Parameters

Summarize the draws of the named parameters as a point estimate (median or mean) and a credible interval (quantile or highest-density), one row per parameter per interval width.

Usage

draws_interval(
  object,
  ...,
  .width = 0.95,
  .point = c("median", "mean"),
  .interval = c("qi", "hdi")
)

# S3 method for class 'ratiod_fit'
draws_interval(
  object,
  ...,
  .width = 0.95,
  .point = c("median", "mean"),
  .interval = c("qi", "hdi")
)

Arguments

object

A ratiod_fit object

...

Parameter names to summarize (unquoted).

.width

Width(s) of credible intervals. Default 0.95.

.point

Point estimate function: "median" (default) or "mean".

.interval

Interval type: "qi" for quantile interval (default), "hdi" for highest density interval.

Value

A data frame with columns for the variable name, point estimate, and interval bounds.

Examples

# \donttest{
# Generate synthetic data
set.seed(444)
n <- 48
site <- rep(letters[1:12], each = 4)
u <- rnorm(12, sd = 0.5)[match(site, letters[1:12])]
depth <- rnorm(n)
df <- data.frame(
  count = rpois(n, exp(3 + 0.3 * depth + u)),
  effort = rgamma(n, shape = 9, rate = exp(-u)),
  depth = depth,
  site = site
)

# Fit model
fit <- tratio(
  count | effort ~ depth + (1 | site),
  data = df,
  family = ratiod_poisson_gamma(),
  mode = "hmc",
  control = list(iter = 400, chains = 1, seed = 1)
)

# Get point estimates and 95% intervals
draws_interval(fit, beta_num, beta_denom)
#>       .variable     .value    .lower    .upper .width .point .interval
#> 1   beta_num[1] 2.83592365  2.577034 3.0446831   0.95 median        qi
#> 2   beta_num[2] 0.27202611  0.213629 0.3513051   0.95 median        qi
#> 3 beta_denom[1] 1.96086762  1.692588 2.1988844   0.95 median        qi
#> 4 beta_denom[2] 0.02074274 -0.080992 0.1155757   0.95 median        qi

# Multiple interval widths
draws_interval(fit, beta_num, .width = c(0.5, 0.9, 0.95))
#>     .variable    .value    .lower    .upper .width .point .interval
#> 1 beta_num[1] 2.8359236 2.7581830 2.8927646   0.50 median        qi
#> 2 beta_num[1] 2.8359236 2.6095587 3.0191710   0.90 median        qi
#> 3 beta_num[1] 2.8359236 2.5770341 3.0446831   0.95 median        qi
#> 4 beta_num[2] 0.2720261 0.2477747 0.3059871   0.50 median        qi
#> 5 beta_num[2] 0.2720261 0.2206847 0.3378846   0.90 median        qi
#> 6 beta_num[2] 0.2720261 0.2136290 0.3513051   0.95 median        qi
# }