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Occupancy with both false negatives and false positives in the detection process (e.g. acoustic classifiers, citizen-science misidentification), using the Miller et al. (2011) confirmed-detection design that makes the model robustly identifiable. Each visit yields a detection state y in {0, 1, 2}: 0 = no detection, 1 = ambiguous detection (a true detection OR a false positive), 2 = certain / confirmed detection (only possible when the site is truly occupied). The latent occupancy z marginalises in closed form (two states), so the fit maximises the exact marginal likelihood directly (analytic-gradient BFGS, observed-information covariance) with a NUTS path over the same marginal.

Usage

fp_occu()

Value

A tobs_family object.

Details

Four site-level logit arms: occupancy psi (the tobs() formula), true detection p11 (detection), false-positive rate p10, and the probability a true detection is certain b. The p10 and b predictors default to intercept-only and are set with the p10 = ~ ... and certainty = ~ ... arguments to tobs() (certainty is the b arm). The response y is an n_sites x J integer matrix in {0, 1, 2} (NA visits dropped).

References

Miller, D. A. W., Nichols, J. D., McClintock, B. T., Grant, E. H. C., Bailey, L. L., Weir, L. A. (2011). Improving occupancy estimation when two types of observational error occur. Ecology 92, 1422-1428. Royle, J. A., Link, W. A. (2006). Generalized site occupancy models allowing for false positive and false negative errors. Ecology 87, 835-841.

Examples

f <- fp_occu()
f