inst/examples/affinity_example.R

In CooccurrenceAffinity: Affinity in Co-Occurrence Data

# when you have a binary presence absence occurrence data
# -------------------------------------------------------

if(requireNamespace("cooccur", quietly = TRUE)) {
  data(finches, package = "cooccur")
} else {
  message("The cooccur package is not installed.
          You can install it with install.packages('cooccur').")
}

data(finches, package = "cooccur")



# the remainder of the script has been enclosed under \donttest{}
# to bypass the CRAN's 5 second limit on example files
# --------------------------------------------------------------

\donttest{


head(finches)
# this dataset carries the occurrence records of 13 species in row in 17 islands in columns
dim(finches)

# compute alpha and other quantities for island-pair affinity (beta diversity)
myout <- affinity(data = finches, row.or.col = "col")
myout

# you can simply flip the analysis to rows to compute species-pair affinity
myout <- affinity(data = finches, row.or.col = "row")
myout



# the rows of the outputs above include every single pair of the entities,
# producing many columns for various quantities.
# for several of these columns, the function allows outputing the square NxN matrix of the entities
# an example is here
myout <- affinity(data = finches, row.or.col = "col", squarematrix = c("alpha_mle", "jaccard"))
# it is a list of three elements: one main dataframe and two square matrices
length(myout)
myout
head(myout)

# you can also compute all the square matrices with an "all"
myout <- affinity(data = finches, row.or.col = "col", squarematrix = c("all"))
# this one has 12 elements
length(myout)
myout

# when you want to compute for only certain pairs
myout <- affinity(data = finches, row.or.col = "col", which.row.or.col = 4:6,
                  squarematrix = c("alpha_mle"))
myout

myout <- affinity(data = finches, row.or.col = "col",
                  which.row.or.col = c("Isabella", "Espanola"), squarematrix = c("alpha_mle"))
myout

} #end of \donttest{}



# if you select only one column, the computation stops
\dontrun{
  myout <- affinity(data = finches, row.or.col = "col",
                    which.row.or.col = c("Darwin"), squarematrix = c("alpha_mle"))
}



\donttest{

# you can also add additional arguments bringing them from ML.Alpha() or AlphInts()
myout1 <- affinity(data = finches, row.or.col = "col",
                   which.row.or.col = c("Isabella", "Espanola"), lev=0.95, pvalType="Blaker")
myout1
myout2 <- affinity(data = finches, row.or.col = "col",
                   which.row.or.col = c("Isabella", "Espanola"), lev=0.90, pvalType="Blaker")
myout2
identical(myout1, myout2)
# myout1 and myout2 were generated with identical arguments except a difference in "lev",
# which gave different confidence intervals

myout3 <- affinity(data = finches, row.or.col = "col",
                   which.row.or.col = 4:6, lev=0.95, pvalType="Blaker")
myout3
myout4 <- affinity(data = finches, row.or.col = "col",
                   which.row.or.col = 4:6, lev=0.95, pvalType="midP")
myout4
myout3$all$p_value
myout4$all$p_value
# the p values are (or, can be) different

# when you have abundance data requiring conversion to binary
# -----------------------------------------------------------
# abundance data is converted to binary based on a threshold supplied.
# it might be a good idea to explore dataprep() function and its examples
# first before workign on affinity() for abundance data.
matrix.data <- matrix(runif(400, 0, 10), nrow = 100, ncol = 4)
row.names(matrix.data) <- paste0("id_", 1:nrow(matrix.data))
colnames(matrix.data) <- paste0("variable_", 1:ncol(matrix.data))

# add some missing data and zero abundance
matrix.data[1,1] <- matrix.data[2,3] <- matrix.data[1,4] <- matrix.data[1,2] <- NA
matrix.data[10,4] <- 0
head(matrix.data)
# now this is an abundance data with some missing and some zero occurrences

# inspecting how the abundance is converted to binary first
dataprep(data = matrix.data, row.or.col = "col", datatype = "abundance",
         threshold = 5, class0.rule = "less")
myout10 <- affinity(data = matrix.data, row.or.col = "col",
                    datatype = "abundance", threshold = 5, class0.rule = "less")
myout10

# you can also feed the output of dataprep() to affinity()
myinput <- dataprep(data = matrix.data, row.or.col = "col",
                    datatype = "abundance", threshold = 5, class0.rule = "less")
myout11 <- affinity(data = myinput, row.or.col = "col", datatype = "binary")
myout11
# myout 10 and myout11 are identical
identical(myout10, myout11)

} # end of \donttest{}