nec: Extracts the predicted NEC value as desired from an object of class
bayesnecfit
or bayesmanecfit
.
Description
Extracts the predicted NEC value as desired from an object of class
bayesnecfit
or bayesmanecfit
.
Usage
nec(
object,
posterior = FALSE,
xform = identity,
prob_vals = c(0.5, 0.025, 0.975)
)
Value
A vector containing the estimated NEC value, including upper and
lower 95% credible interval bounds (or other interval as specified by
prob_vals).
Arguments
- object
An object of class bayesnecfit
or
bayesmanecfit
returned by bnec
.
- posterior
A logical
value indicating if the full
posterior sample of calculated NEC values should be returned instead of
just the median and 95% credible intervals.
- xform
A function to apply to the returned estimated concentration
values.
- prob_vals
A vector indicating the probability values over which to
return the estimated NEC value. Defaults to 0.5 (median) and 0.025 and
0.975 (95 percent credible intervals).
Details
The NEC is a parameter in a threshold model (for example,
see Fox 2010), and is a true measure
of No-effect-concentration (the minimum concentration above which an effect
is predicted to occur.
References
Fox DR (2010). A Bayesian Approach for Determining the No Effect
Concentration and Hazardous Concentration in Ecotoxicology. Ecotoxicology
and Environmental Safety, 73(2), 123–131. doi: 10.1016/j.ecoenv.2009.09.012.
Examples
Run this codelibrary(bayesnec)
data(manec_example)
nec(manec_example)
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