This function fits model Mtb for closed populations in capture-recapture experiments.
closedp.Mtb(X, dfreq=FALSE, method = "BFGS", …)
# S3 method for closedp.Mtb print(x, …)
The matrix of the observed capture histories (see
Rcapture-package for a description of the accepted formats).
A logical. By default
FALSE, which means that
X has one row per unit. If TRUE, it
indicates that the matrix
X contains frequencies in its last column.
The method to be used by
optim. The default is
An object, produced by the
closedp.Mtb function, to print.
The number of captured units
The total number of capture occasions in the data matrix
A table containing, for the fitted model:
: the estimated population size,
: the standard error of the estimated population size,
: the model's deviance,
: the number of degrees of freedom,
: the Akaike's information criterion,
: the bayesian information criterion,
: a numerical code giving information about error or warnings
encountered when fitting the model (see
Rcapture-package for details).
The output produced by
optim from fitting the model.
A vector of character strings. If the
optim function generates
one or more warnings when fitting the model, a copy of these warnings are
optim did not produce
Capture-recapture parameters estimates for model Mtb : the abundance N, \(p_1\) to \(p_t\), the probabilities of first capture for each capture occasion, and \(c_2\) to \(c_t\), the recapture probabilities for each capture occasion.
The Mtb model is non-linear. It is fitted with the
optim function instead of the
glm function. Therefore, the abundance estimate can be unstable.
For the model to be identifiable, the parameters are constrained in the following way: \(logit(c_i)=logit(p_i)+b\) for i in \(2,\ldots,l\).
Baillargeon, S. and Rivest, L.P. (2007) Rcapture: Loglinear models for capture-recapture in R. Journal of Statistical Software, 19(5), http://www.jstatsoft.org/v19/i05.