point.est.rm: Removal Method Method Abundance Estimation: Point Estimate

In dill/wisp: Wildlife Simulation Package (wisp)

Description

This function estimates abundance and related parameters from a simple removal method sample object (of class ‘sample.rm’).

Usage

        point.est.rm(samp, numerical = TRUE, plot = FALSE)

Arguments

samp	object of class 'sample.rm´.
numerical	If TRUE the estimator will be calculated by maximising the likelihood derived in "Borchers, Buckland and Zucchini", equation 5.4. If FALSE the estimator will be calculated analytically. The analytic estimator is only available for exactly two survey occasions.
plot	If TRUE a plot of the cumulative removals and the resulting estimator will be generated.

Value

An object of class 'point.est.rm´ containing the following items:

sample	The data contained in the sample object
numerical	Equal to the object 'numerical' passed to the function
Nhat.grp	MLE of group abundance
Nhat.ind	MLE of individual abundance (= Nhat.grp * Es)
phat	Estimate(s) of capture probability for the relevant model (try it and see)
Es	Estimate of mean group size (simple mean of observed group sizes)
log.Likelihood	Value of log-likelihood at MLE
AIC	Akaike's information criterion
parents	Details of WiSP objects passed to function
created	Creation date and time

See Also

setpars.survey.rm, generate.sample.rm int.est.rm

Examples

rm.reg<-generate.region(x.length=100, y.width=50)

rm.dens <- generate.density(rm.reg)
rm.poppars<-setpars.population(density.pop = rm.dens, number.groups = 100, size.method = "poisson", 
						size.min = 1, size.max = 5, size.mean = 1, exposure.method = "beta", 
						exposure.min = 2, exposure.max = 10, exposure.mean = 3, exposure.shape = 0.5, 
						type.values=c("Male","Female"), type.prob=c(0.48,0.52))
rm.pop<-generate.population(rm.poppars)

rm.des<-generate.design.rm(rm.reg, n.occ = 5, effort=c(1,2,3,2,1))
rm.survpars<-setpars.survey.rm(pop=rm.pop, des=rm.des, pmin=0.03, pmax=0.95, improvement=0.05)
rm.samp<-generate.sample.rm(rm.survpars)

rm.est<-point.est.rm(rm.samp)
summary(rm.est)

dill/wisp documentation built on May 15, 2019, 8:31 a.m.