Get QPAD offsets
wt_qpad_offsets.Rd
This function calculates statistical offsets that account for survey-specific and species-specific variation in availability for detection and perceptibility of birds. This function requires download of the QPAD
R package and should be used on the output of the wt_make_wide()
function
Usage
wt_qpad_offsets(data, species = c("all"), version = 3, together = FALSE)
Arguments
- data
Dataframe output from the
wt_make_wide()
function.- species
Character; species for offset calculation. Can be a list of 4-letter AOU codes (e.g., c("TEWA", "OSFL", "OVEN")) or "all" to calculate offsets for every species in the input dataframe for which offsets are available. Defaults to "all".
- version
Numeric; version of QPAD offsets to use (2, or 3). Defaults to 3.
- together
Logical; whether or not offsets should be bound to the input dataframe or returned as a separate object.
Value
A dataframe containing the QPAD values either by themselves or with the original wide data if together = TRUE
References
Solymos et al. 2013. Calibrating indices of avian density from non-standardized survey data: making the most of a messy situation. Methods in Ecology and Evolution, 4, 1047-1058.
Examples
if (FALSE) { # \dontrun{
devtools::install_github("borealbirds/QPAD")
dat.clean <- wt_tidy_species(dat)
dat.tmtt <- wt_replace_tmtt(dat.clean)
dat.wide <- wt_make_wide(dat.tmtt, sound="all")
dat.qpad <- wt_qpad_offsets(dat.wide, species="all", version=3, together = TRUE)
} # }