
Monte Carlo Node Specifications for the Water Supply Example
Source:R/data_water.R
water_mctable.RdA configured Monte Carlo node table for the illustrative water-supply risk assessment. It defines the input nodes, probability distributions, and sampling ranges used to evaluate the treatment and intrusion pathways.
Format
A data frame with 8 rows and 7 columns:
- mcnode
Name of the Monte Carlo input node.
- description
Description of the represented parameter.
- mc_func
Random-number generation function.
NAidentifies a deterministic input.- from_variable
Alternative source column used to create the node, where applicable.
- transformation
Transformation applied to the source values, where applicable.
- sensi_variation
Expression defining variation for one-at-a-time sensitivity analysis.
- sample_space
Sampling range or distribution arguments used for sample-design sensitivity analysis.
Source
Parameter ranges are illustrative. They do not represent a fitted model for a specific water system.
Details
source_conc and treatment_lrv use PERT distributions, while
intrusion_conc uses a uniform distribution. The remaining inputs are
deterministic in the main Monte Carlo model. The sample_space values
provide illustrative ranges for optional sample-design sensitivity
analyses.
Examples
water_mctable
#> mcnode
#> 1 source_conc
#> 2 treatment_lrv
#> 3 water_volume
#> 4 intrusion_prob
#> 5 intrusion_conc
#> 6 dose_response_r
#> 7 population
#> 8 exposure_days
#> description mc_func
#> 1 Cryptosporidium concentration in source water (oocysts/L) rpert
#> 2 Cryptosporidium log10 reduction during treatment rpert
#> 3 Daily consumption of unboiled tap water (L/person/day) <NA>
#> 4 Daily probability that a distribution zone is affected by intrusion <NA>
#> 5 Cryptosporidium concentration if intrusion occurs (oocysts/L) runif
#> 6 Exponential Cryptosporidium dose-response parameter <NA>
#> 7 Population exposed in the distribution zone <NA>
#> 8 Number of daily exposure events <NA>
#> from_variable transformation sensi_variation sample_space
#> 1 <NA> <NA> <NA> min = 0.5, mode = 1.0, max = 1.5
#> 2 <NA> <NA> <NA> min = 2.5, mode = 3.0, max = 3.5
#> 3 <NA> <NA> <NA> min = 1.0, max = 2.0
#> 4 <NA> <NA> <NA> min = 0.0002, max = 0.005
#> 5 <NA> <NA> <NA> min = 0.01, max = 0.05
#> 6 <NA> <NA> <NA> c(0.018, 0.018)
#> 7 <NA> <NA> <NA> <NA>
#> 8 <NA> <NA> <NA> c(30, 30)