ethnobotanyR package functions
The use report
URs() function calculates the use report (UR) for each species in the data set.
\[\begin{equation}
UR_{s} = \sum_{u=u_1}^{^uNC} \sum_{i=i_1}^{^iN} UR_{ui}
\end{equation}\]
URs() calculates the total uses for the species by all informants (from \(i_1\) to \(^iN\)) within each use-category for that species \((s)\). It is a count of the number of informants who mention each use-category \(NC\) for the species and sums all those uses in each use-category (from \(u_1\) to \(^uNC\)).
ethnobotanyR::URs(ethnobotanydata)
#> [1] "Total number of Use Reports (URs) for each species in the data set"
#> sp_name URs
#> 3 sp_c 52
#> 1 sp_a 43
#> 4 sp_d 43
#> 2 sp_b 36
The URsum() function calculates the sum of all ethnobotany use reports (UR) for all species in the data set.
ethnobotanyR::URsum(ethnobotanydata)
#> [1] "Sum of all Use Reports (UR) for all species in the data set"
#> [1] 174
The
CIs() function calculates the Cultural Importance Index (CI) for each species in the data set.
\[\begin{equation}
CI_{s} = \sum_{u=u_1}^{^uNC} \sum_{i=i_1}^{^iN} UR_{ui/N}.
\end{equation}\]
CIs() is essentially URs() divided by the number of informants to account for the diversity of uses for the species.
ethnobotanyR::CIs(ethnobotanydata)
#> [1] "Cultural Importance index (CI) for each species in the data set"
#> sp_name Ci
#> 3 sp_c 0.2363636
#> 1 sp_a 0.1954545
#> 4 sp_d 0.1954545
#> 2 sp_b 0.1636364
The
FCs() function calculates the frequency of citation (FC) for each species in the data set.
\[\begin{equation}
FC_s = \sum_{i=i_1}^{^iN} UR_i
\end{equation}\]
FCs() is the sum of informants that cite a use for the species.
ethnobotanyR::FCs(ethnobotanydata)
#> [1] "Frequency of citation (FC) for each species in the data set"
#> sp_name FCs
#> 3 sp_c 17
#> 1 sp_a 15
#> 2 sp_b 12
#> 4 sp_d 12
The
NUs() function calculates the number of uses (NU) for each species in the data set.
\[\begin{equation}
NU_s = \sum_{u=u_1}^{^uNC}
\end{equation}\]
\(NC\) are the number of use categories. NUs() is the sum of all categories for which a species is considered useful.
ethnobotanyR::NUs(ethnobotanydata)
#> [1] "Number of Uses (NU) for each species in the data set"
#> sp_name NUs
#> 3 sp_c 8
#> 4 sp_d 8
#> 1 sp_a 7
#> 2 sp_b 7
The
RFCs() function calculates the relative frequency of citation (RFC) for each species in the data set.
\[\begin{equation}
RFC_s = \frac{FC_s}{N} = \frac{\sum_{i=i_1}^{^iN} UR_i}{N}
\end{equation}\]
\(FC_s\) is the frequency of citation for each species \(s\), \(UR_i\) are the use reports for all informants \(i\) and \(N\) is the total number of informants interviewed in the survey.
ethnobotanyR::RFCs(ethnobotanydata)
#> [1] "Relative Frequency of Citation (RFC) for each species in the data set"
#> sp_name RFCs
#> 3 sp_c 0.85
#> 1 sp_a 0.75
#> 2 sp_b 0.60
#> 4 sp_d 0.60
The
RIs() function calculates the relative importance index (RI) for each species in the data set.
\[\begin{equation}
RI_s = \frac{RFC_{s(max)} + RNU_{s(max)}}{2}
\end{equation}\]
\(RFC_{s(max)}\) is the relative frequency of citation for the species \(s\) over the maximum, \(RNU_{s(max)}\) is the relative number of uses for \(s\) over the maximum.
ethnobotanyR::RIs(ethnobotanydata)
#> [1] "Relative Importance Index (RI) for each species in the data set"
#> sp_name RIs
#> 3 sp_c 1.000
#> 1 sp_a 0.879
#> 4 sp_d 0.853
#> 2 sp_b 0.790
The
UVS() function calculates the use value (UV) index for each species in the data set.
\[\begin{equation}
UV_{s} = \sum U_i/N
\end{equation}\]
\(U_i\) is the number of different uses mentioned by each informant \(i\) and \(N\) is the total number of informants interviewed in the survey.
ethnobotanyR::UVs(ethnobotanydata)
#> [1] "Use Value index (UV) for each species in the data set"
#> sp_name UVs
#> 3 sp_c 2.60
#> 1 sp_a 2.15
#> 4 sp_d 2.15
#> 2 sp_b 1.80
ethnobotanyR chord diagrams ith circlize
The following chord plots are made using functions from the circlize package. An example of the application of chord plots in ethnobotany is described by Whitney et al. (2018).
The ethnoChord() function creates a chord diagram of ethnobotany uses and species.
ethnobotanyR::ethnoChord(ethnobotanydata)
#> [1] "Chord diagram for each use related to each species in the data set"
The ethnoChordUser() function creates a chord diagram of informants and species uses for ethnobotany studies.
ethnobotanyR::ethnoChordUser(ethnobotanydata)
#> [1] "Chord diagram for each use related to each informant in the data set"
References
Tardio, J., and M. Pardo-de-Santayana, 2008. Cultural Importance Indices: A Comparative Analysis Based on the Useful Wild Plants of Southern Cantabria (Northern Spain) 1. Economic Botany, 62(1), 24-39. https://doi.org/10.1007/s12231-007-9004-5.
Whitney, C. W., Bahati, J., and Gebauer, J. (2018), Ethnobotany and agrobiodiversity; valuation of plants in the homegardens of southwestern Uganda. Ethnobiology Letters, 9(2), 90-100. https://doi.org/10.14237/ebl.9.2.2018.503