Simulate data for developing project prioritizations. Here, data are simulated such that each feature has its own conservation project, similar to species-based prioritizations (e.g. Bennett et al. 2014).

simulate_ppp_data(
  number_features,
  cost_mean = 100,
  cost_sd = 5,
  success_min_probability = 0.7,
  success_max_probability = 0.99,
  funded_min_persistence_probability = 0.5,
  funded_max_persistence_probability = 0.9,
  baseline_min_persistence_probability = 0.01,
  baseline_max_persistence_probability = 0.4,
  locked_in_proportion = 0,
  locked_out_proportion = 0
)

Arguments

number_features

numeric number of features.

cost_mean

numeric average cost for the actions. Defaults to 100.

cost_sd

numeric standard deviation in action costs. Defaults to 5.

success_min_probability

numeric minimum probability of the projects succeeding if they are funded. Defaults to 0.7.

success_max_probability

numeric maximum probability of the projects succeeding if they are funded. Defaults to 0.99.

funded_min_persistence_probability

numeric minimum probability of the features persisting if projects are funded and successful. Defaults to 0.5.

funded_max_persistence_probability

numeric maximum probability of the features persisting if projects are funded and successful. Defaults to 0.9.

baseline_min_persistence_probability

numeric minimum probability of the features persisting if only the baseline project is funded. Defaults to 0.01.

baseline_max_persistence_probability

numeric maximum probability of the features persisting if only the baseline project is funded. Defaults to 0.4.

locked_in_proportion

numeric of actions that are locked into the solution. Defaults to 0.

locked_out_proportion

numeric of actions that are locked into the solution. Defaults to 0.

Value

A list object containing the elements:

"projects"

A tibble::tibble() containing the data for the conservation projects. It contains the following columns:

"name"

character name for each project.

"success"

numeric probability of each project succeeding if it is funded.

"F1" ... "FN"

numeric columns for each feature, ranging from "F1" to "FN" where N is the number of features, indicating the enhanced probability that each feature will persist if it funded. Missing values (NA) indicate that a feature does not benefit from a project being funded.

"F1_action" ... "FN_action"

logical columns for each action, ranging from "F1_action" to "FN_action" where N is the number of actions (equal to the number of features in this simulated data), indicating if an action is associated with a project (TRUE) or not (FALSE).

"baseline_action"

logical column indicating if a project is associated with the baseline action (TRUE) or not (FALSE). This action is only associated with the baseline project.

"actions"

A tibble::tibble() containing the data for the conservation actions. It contains the following columns:

"name"

character name for each action.

"cost"

numeric cost for each action.

"locked_in"

logical indicating if certain actions should be locked into the solution.

"locked_out"

logical indicating if certain actions should be locked out of the solution.

"features"

A tibble::tibble() containing the data for the conservation features (e.g. species). It contains the following columns:

"name"

character name for each feature.

"weight"

numeric weight for each feature. For each feature, this is calculated as the amount of time that elapsed between the present and the features' last common ancestor. In other words, the weights are calculated as the unique amount of evolutionary history that each feature has experienced.

"tree"

ape::phylo() phylogenetic tree for the features.

Details

The simulated data set will contain one conservation project for each features, and also a "baseline" (do nothing) project to reflect features' persistence when their conservation project is not funded. Each conservation project is associated with a single action, and no conservation projects share any actions. Specifically, the data are simulated as follows:

  1. A conservation project is created for each feature, and each project is associated with its own single action.

  2. Cost data for each action are simulated using a normal distribution and the cost_mean and cost_sd arguments.

  3. A set proportion of the actions are randomly set to be locked in and out of the solutions using the locked_in_proportion and locked_out_proportion arguments.

  4. The probability of each project succeeding if its action is funded is simulated by drawing probabilities from a uniform distribution with the upper and lower bounds set as the success_min_probability and success_max_probability arguments.

  5. The probability of each feature persisting if its project is funded and is successful is simulated by drawing probabilities from a uniform distribution with the upper and lower bounds set as the funded_min_persistence_probability and funded_max_persistence_probability arguments.

  6. An additional project is created which represents the "baseline" (do nothing) scenario. The probability of each feature persisting when managed under this project is simulated by drawing probabilities from a uniform distribution with the upper and lower bounds set as the baseline_min_persistence_probability and baseline_max_persistence_probability arguments.

  7. A phylogenetic tree is simulated for the features using ape::rcoal().

  8. Feature data are created from the phylogenetic tree. The weights are calculated as the amount of evolutionary history that has elapsed between each feature and its last common ancestor.

References

Bennett JR, Elliott G, Mellish B, Joseph LN, Tulloch AI, Probert WJ, ... & Maloney R (2014) Balancing phylogenetic diversity and species numbers in conservation prioritization, using a case study of threatened species in New Zealand. Biological Conservation, 174: 47--54.

Examples

# create a simulated data set
s <- simulate_ppp_data(number_features = 5,
                       cost_mean = 100,
                       cost_sd = 5,
                       success_min_probability = 0.7,
                       success_max_probability = 0.99,
                       funded_min_persistence_probability = 0.5,
                       funded_max_persistence_probability = 0.9,
                       baseline_min_persistence_probability = 0.01,
                       baseline_max_persistence_probability = 0.4,
                       locked_in_proportion = 0.01,
                       locked_out_proportion = 0.01)

# print data set
print(s)
#> $projects
#> # A tibble: 6 × 13
#>   name  success     F1     F2     F3     F4     F5 F1_action F2_action F3_action
#>   <chr>   <dbl>  <dbl>  <dbl>  <dbl>  <dbl>  <dbl> <lgl>     <lgl>     <lgl>    
#> 1 F1_p…   0.711  0.830 NA     NA     NA     NA     TRUE      FALSE     FALSE    
#> 2 F2_p…   0.879 NA      0.516 NA     NA     NA     FALSE     TRUE      FALSE    
#> 3 F3_p…   0.728 NA     NA      0.872 NA     NA     FALSE     FALSE     TRUE     
#> 4 F4_p…   0.809 NA     NA     NA      0.518 NA     FALSE     FALSE     FALSE    
#> 5 F5_p…   0.944 NA     NA     NA     NA      0.578 FALSE     FALSE     FALSE    
#> 6 base…   1      0.174  0.335  0.199  0.343  0.240 FALSE     FALSE     FALSE    
#> # ℹ 3 more variables: F4_action <lgl>, F5_action <lgl>, baseline_action <lgl>
#> 
#> $actions
#> # A tibble: 6 × 4
#>   name             cost locked_in locked_out
#>   <chr>           <dbl> <lgl>     <lgl>     
#> 1 F1_action        105. FALSE     FALSE     
#> 2 F2_action        110. TRUE      FALSE     
#> 3 F3_action        104. FALSE     FALSE     
#> 4 F4_action        100. FALSE     FALSE     
#> 5 F5_action        105. FALSE     TRUE      
#> 6 baseline_action    0  FALSE     FALSE     
#> 
#> $features
#> # A tibble: 5 × 2
#>   name  weight
#>   <chr>  <dbl>
#> 1 F1     0.483
#> 2 F2     0.170
#> 3 F3     0.170
#> 4 F4     0.247
#> 5 F5     0.499
#> 
#> $tree
#> 
#> Phylogenetic tree with 5 tips and 4 internal nodes.
#> 
#> Tip labels:
#>   F1, F2, F3, F4, F5
#> 
#> Rooted; includes branch lengths.
#>