evaluate_experiment: Evaluate an 'Experiment'.

In Yu-Group/simChef: Intensive Computational Experiments Made Easy

Evaluate an Experiment.

Description

Evaluate the performance of method(s) across all Evaluators in the Experiment and return results.

Usage

evaluate_experiment(
  experiment,
  fit_results,
  use_cached = FALSE,
  save = FALSE,
  verbose = 1,
  ...
)

Arguments

experiment	An Experiment object.
fit_results	A tibble, as returned by fit_experiment().
use_cached	Logical. If TRUE, find and return previously saved results. If cached results cannot be found, continue as if use_cached was FALSE.
save	If TRUE, save outputs to disk.
verbose	Level of verbosity. Default is 1, which prints out messages after major checkpoints in the experiment. If 2, prints additional debugging information for warnings and messages from user-defined functions (in addition to error debugging information). If 0, no messages are printed other than user-defined function error debugging information.
...	Not used.

Value

A list of evaluation result tibbles, one for each Evaluator.

Examples

## create toy DGPs, Methods, Evaluators, and Visualizers

# generate data from normal distribution with n samples
normal_dgp <- create_dgp(
  .dgp_fun = function(n) rnorm(n), .name = "Normal DGP", n = 10
)
# generate data from binomial distribution with n samples
bernoulli_dgp <- create_dgp(
  .dgp_fun = function(n) rbinom(n, 1, 0.5), .name = "Bernoulli DGP", n = 10
)

# compute mean of data
mean_method <- create_method(
  .method_fun = function(x) list(mean = mean(x)), .name = "Mean(x)"
)

# evaluate SD of mean(x) across simulation replicates
sd_mean_eval <- create_evaluator(
  .eval_fun = function(fit_results, vary_params = NULL) {
    group_vars <- c(".dgp_name", ".method_name", vary_params)
    fit_results %>%
      dplyr::group_by(dplyr::across(tidyselect::all_of(group_vars))) %>%
      dplyr::summarise(sd = sd(mean), .groups = "keep")
  },
  .name = "SD of Mean(x)"
)

# plot SD of mean(x) across simulation replicates
sd_mean_plot <- create_visualizer(
  .viz_fun = function(fit_results, eval_results, vary_params = NULL,
                      eval_name = "SD of Mean(x)") {
    if (!is.null(vary_params)) {
      add_aes <- ggplot2::aes(
        x = .data[[unique(vary_params)]], y = sd, color = .dgp_name
      )
    } else {
      add_aes <- ggplot2::aes(x = .dgp_name, y = sd)
    }
    plt <- ggplot2::ggplot(eval_results[[eval_name]]) +
      add_aes +
      ggplot2::geom_point()
    if (!is.null(vary_params)) {
      plt <- plt + ggplot2::geom_line()
    }
    return(plt)
  },
  .name = "SD of Mean(x) Plot"
)

# initialize experiment with toy DGPs, Methods, Evaluators, and Visualizers
experiment <- create_experiment(
  name = "Experiment Name",
  dgp_list = list(`Normal DGP` = normal_dgp, `Bernoulli DGP` = bernoulli_dgp),
  method_list = list(`Mean(x)` = mean_method),
  evaluator_list = list(`SD of Mean(x)` = sd_mean_eval),
  visualizer_list = list(`SD of Mean(x) Plot` = sd_mean_plot)
)

# initialize empty experiment with user-defined directory for saving results
experiment <- create_experiment(
  name = "Experiment Name",
  dgp_list = list(`Normal DGP` = normal_dgp, `Bernoulli DGP` = bernoulli_dgp),
  method_list = list(`Mean(x)` = mean_method),
  evaluator_list = list(`SD of Mean(x)` = sd_mean_eval),
  visualizer_list = list(`SD of Mean(x) Plot` = sd_mean_plot),
  save_dir = 'path/to/directory'
)

# initialize experiment with toy DGPs, Methods, Evaluators, and Visualizers
# using piping %>%
experiment <- create_experiment(name = "Experiment Name") %>%
  add_dgp(normal_dgp) %>%
  add_dgp(bernoulli_dgp) %>%
  add_method(mean_method) %>%
  add_evaluator(sd_mean_eval) %>%
  add_visualizer(sd_mean_plot)

# run experiment with 2 replicates
results <- run_experiment(experiment, n_reps = 2)
# uncomment below to view results
# results

# run experiment with varying number of samples n
experiment <- experiment %>%
  add_vary_across(
    .dgp = c("Normal DGP", "Bernoulli DGP"), n = c(1, 10)
  )
# run vary-across experiment with 2 replicates
results <- run_experiment(experiment, n_reps = 2)
# uncomment below to view results
# results

# `run_experiment()` above is equivalent to the following sequence of calls
fit_results <- fit_experiment(experiment, n_reps = 2)
eval_results <- evaluate_experiment(experiment, fit_results)
viz_results <- visualize_experiment(experiment, fit_results, eval_results)

# generate data from all DGPs (and vary across components) in experiment
data_out <- generate_data(experiment, n_reps = 1)

Yu-Group/simChef documentation built on March 25, 2024, 3:22 a.m.