Start elicitation

cat_start() initialises an elic_cat object which stores important metadata for the data collected during the elicitation process of categorical data.

Usage

cat_start(
  categories,
  options,
  experts,
  topics,
  ...,
  title = "Elicitation",
  verbose = TRUE
)

Arguments

categories

character vector with the names of the categories. See Categories for more.

options

character vector with the names of all options investigated. See Options for more.

experts

numeric, indicating the maximum number of experts participating in the elicitation process for one topic. See Experts for more.

topics

character vector with the names of the topics.

...

Unused arguments, included only for future extensions of the function.

title

character, used to bind a name to the object.

verbose

logical, if TRUE it prints informative messages.

Value

An object of class elic_cat binding metadata related to the elicitation process. These metadata are used by other functions to validate the correctness of the provided data.

Categories

Categories are inherited between topics. A minimum of two categories are needed. If only one category is investigated, please refer to the functions for the elicitation of continuous data (e.g. cont_start).

Options

The option parameter is a character vector containing the names of all the options investigated in the elicitation. However, not all options have to be investigated in every topic.

Experts

The expert parameter is a number indicating the maximum number of experts taking part in the elicitation of one of the investigated topics. The number and IDs of experts can differ between the topics.

References

Hemming, V., Burgman, M. A., Hanea, A. M., McBride, M. F., & Wintle, B. C. (2018). A practical guide to structured expert elicitation using the IDEA protocol. Methods in Ecology and Evolution, 9(1), 169–180. https://doi.org/10.1111/2041-210X.12857 Vernet, M., Trask, A.E., Andrews, C.E., Ewen, J.E., Medina, S., Moehrenschlager, A. & Canessa, S. (2024) Assessing invasion risks using EICAT‐based expert elicitation: application to a conservation translocation. Biological Invasions, 26(8), 2707–2721. https://doi.org/10.1007/s10530-024-03341-2

See also

Other cat data helpers: cat_add_data(), cat_get_data(), cat_sample_data(), summary.cat_sample()

Author

Sergio Vignali and Maude Vernet

Examples

# Create the elic_cat object for an elicitation process over 2 topics, 3
# options, 3 categories per options, and a maximum number of 8 experts per
# topic
my_categories <- c("category_1", "category_2", "category_3")
my_elicit <- cat_start(categories = my_categories,
                       options = c("option_1", "option_2", "option_3"),
                       experts = 8,
                       topics = c("topic_1","topic_2"))
#> ✔ <elic_cat> object for "Elicitation" correctly initialised
my_elicit
#> 
#> ── Elicitation ──
#> 
#> • Categories: "category_1", "category_2", and "category_3"
#> • Options: "option_1", "option_2", and "option_3"
#> • Number of experts: 8
#> • Topics: "topic_1" and "topic_2"
#> • Data available for 0 topics

# A title can be added to bind a name to the object:
my_elicit <- cat_start(categories = my_categories,
                       options = c("option_1", "option_2", "option_3"),
                       experts = 8,
                       topics = c("topic_1","topic_2"),
                       title = "My elicitation")
#> ✔ <elic_cat> object for "My elicitation" correctly initialised
my_elicit
#> 
#> ── My elicitation ──
#> 
#> • Categories: "category_1", "category_2", and "category_3"
#> • Options: "option_1", "option_2", and "option_3"
#> • Number of experts: 8
#> • Topics: "topic_1" and "topic_2"
#> • Data available for 0 topics