MS_popan {RMark} | R Documentation |
Convert Multistate data for POPAN-style abundance estimation
Description
Converts data and optionally creates and structures design data list such that population size can be derived with multistate data. Variance estimate is questionable.
Usage
MS_popan(
x,
augment_num = 100,
augment_stratum = "A",
enter_stratum = "B",
strata = NULL,
begin.time = 1,
groups = NULL,
ddl = FALSE,
time.intervals = NULL
)
Arguments
x |
an RMark dataframe |
augment_num |
the number to add with a capture history of all 0s; this is the expected number that were in the population and not ever seen |
augment_stratum |
the single character to represent outside of the population; use a value not used in the data capture history |
enter_stratum |
the single character to represent inside of the population but not yet entered; use a value not used in the data capture history |
strata |
vector of single characters for observed and unobserved states |
begin.time |
beginning time of observed occasions; two occasions are added to the fron of the capture history at times begin.time-1 and begin.time-2 |
groups |
vector of character variable names of factor variables to use for grouping |
ddl |
if TRUE, will return processed data and a design data list with the appropriate fixed parameters. |
time.intervals |
intervals of time between observed occasions |
Author(s)
Jeff Laake
Examples
data(dipper)
popan_N=summary(mark(dipper,model="POPAN",
model.parameters=list(pent=list(formula=~time)),delete=TRUE),se=TRUE)$reals$N
data.list=MS_popan(dipper,ddl=TRUE,augment_num=30)
modMS=mark(data.list$data,data.list$ddl,
model.parameters=list(Psi=list(formula=~B:toB:time)),brief=TRUE,delete=TRUE)
Psi_estimates=summary(modMS,se=TRUE)$reals$Psi
Nhat_MS=Psi_estimates$estimate[1]*sum(abs(data.list$data$data$freq))
se_Nhat_MS=Psi_estimates$se[1]*Nhat_MS
cat("Popan N = ",popan_N$estimate," (se = ",popan_N$se,")\n")
cat("MS N = ",Nhat_MS," (se = ",se_Nhat_MS,")\n")