Computes components of variance for average p=n/N and average p(0) with weights based on empirical covariate distribution, if it contains covariates.
Arguments
- model
ddf model object
- fct
function of detection probabilities; currently only average (over covariates) detection probability p integrated over distance or average (over covariates) detection probability at distance 0; p(0)
- vcov
variance-covariance matrix of parameter estimates
- observer
1,2,3 for primary, secondary, or duplicates for average p(0); passed to fct
- fittedmodel
full fitted ddf model when
trial.fi
orio.fi
is called fromtrial
orio
respectively
Value
- var
variance
- partial
partial derivatives of parameters with respect to fct
- covar
covariance of n and average p or p(0)