ecorisk (version 0.2.1)

calc_exposure: Calculate Overall Exposure Scores from Component-Specific Expert Ratings

Description

Calculate exposure scores from individual exposure components. Additionally calculate associated uncertainty scores.

Usage

calc_exposure(
  pressures,
  components,
  probabilities = NULL,
  uncertainty = NULL,
  method = "mean"
)

Value

Returns a data frame containing the pressure name, the aggregated exposure score and associated uncertainty scores. The results serve as input to the vulnerability

function. In case no uncertainty values were provided, NAs will be returned as uncertainty scores.

Arguments

pressures

A character vector or column of a data frame containing the names of the pressures.

components

A numeric vector or data frame containing the numeric values per exposure component for each pressure. Has to be in the same order as the pressure vector or come from the same data frame.

probabilities

Optionally: a numeric vector containing the probabilities of each pressure (values have to be between 0 and 1); default is NULL. Has to be in the same order as the pressure vector.

uncertainty

a numeric vector or data frame containing the associated uncertainty per component; default is NULL. Has to be in the same order as the pressure vector.

method

a character string specifying the aggregation method. Available are mean (default), median, maximum, and minimum.

Details

Often exposure components include the magnitude of change compared to baseline conditions, the frequency of this change, a future trend and a spatial scale. These components are scored within the ecorisk framework for each pressure by experts on a scale from 1 (low impact) to 5 (high impact). To express their uncertainty during the process, experts can score the associated uncertainty generally for all components of one pressure or for each component individually. The uncertainty is scored in the ecorisk framework on a scale from 1 (low uncertainty) to 3 (high uncertainty). Using exposure and sensitivity scorings vulnerability is calculated. Guidance for the scoring process can be found here: create_template_exposure or in the vignette or in Gutte et al., 2025.

See Also

create_template_exposure, create_template_sensitivity, calc_sensitivity, vulnerability

Examples

### Example using demo data with five pressures, four components and their individual
# uncertainties (probabilities are assumed to be 1):
ex_expert_exposure

calc_exposure(
  pressures = ex_expert_exposure$pressure,
  components = ex_expert_exposure[ ,2:5],
  uncertainty = ex_expert_exposure[ ,6:9]
 )


### Example for two hazardous risks with only two components ('magnitude' and
#   'spatial'), one general uncertainty score, and associated probabilities:
hazard <- c("heat waves", "hurricanes")

# Create scoring table using the template function:
exp_tbl <- create_template_exposure(
  pressures = hazard,
  n_components = 2,
  mode_uncertainty = "general",
  probability = TRUE
)

names(exp_tbl)[2:3] <- c("magnitude", "spatial")
# Assign component-specific scores and probabilities:
exp_tbl$magnitude <- c(5,4)
exp_tbl$spatial <- c(5,3)
exp_tbl$uncertainty <- c(2,3)
exp_tbl$probability <- c(0.8,0.3)

# Calculate exposure score:
calc_exposure(
  pressures = exp_tbl$pressure,
  components = exp_tbl[ ,c("magnitude", "spatial")],
  probabilities = exp_tbl$probability,
  uncertainty = exp_tbl$uncertainty
 )