JS.direct {openCR}

Jolly–Seber Estimates

Description

Non-spatial open-population estimates using the conventional closed-form Jolly–Seber estimators (Pollock et al. 1990).

Usage

JS.direct(object)

Arguments

object

secr capthist object or similar

Details

Estimates are the session-specific Jolly-Seber estimates with no constraints.

The reported SE of births (B) differ slightly from those in Pollock et al. (1990), and may be in error.

Value

A dataframe in which the first 5 columns are summary statistics (counts from JS.counts) and the remaining columns are estimates:

p

capture probability

N

population size

phi

probability of survival to next sample time

B

number of recruits at next sample time

Standard errors are in fields prefixed ‘se’; for N and B these include only sampling variation and omit population stochasticity. The covariance of successive phi-hat is in the field ‘covphi’.

References

Pollock, K. H., Nichols, J. D., Brownie, C. and Hines, J. E. (1990) Statistical inference for capture–recapture experiments. Wildlife Monographs 107. 97pp.

See Also

JS.counts

Examples

# cf Pollock et al. (1990) Table 4.8
JS.direct(microtusCH)