| negLL {MQMF} | R Documentation |
negLL calculate log-normal log-likelihoods
Description
negLL calculates log-normal negative log-likelihoods. It expects the input parameters to be log-transformed, so the funk used to calculate the log or the predicted values also needs to expect log-transformed parameters. In addition, it checks that there are no missing data (NA) within the input observed log-transformed data. If there are it uses only those records for which there are values.
Usage
negLL(pars, funk, logobs, ...)
Arguments
pars |
the log-transformed parameters to be used in the funk for calculating the log of the predicted values against which the log observed values will be compared |
funk |
the function used to calculate the log-predicted values of whatever variable is being used (eg. cpue, catches, etc.) |
logobs |
the observed values, log-transformed, ready for comparison with the log-predicted values from funk and pars. |
... |
required to allow funk to access its other arguments without having to explicitly declare them in negLL. In the example below, indat is passed via the ... |
Value
the negative log-likelihood using log-normal errors.
Examples
data(abdat) # expect an answer of -31.65035
param <- log(c(r= 0.42,K=9400,Binit=3400,sigma=0.05))
negLL(pars=param,funk=simpspm,logobs=log(abdat[,"cpue"]),indat=abdat)