nObs.maxLik {maxLik} | R Documentation |
Returns the number of observations for statistical models
estimated by Maximum Likelihood using maxLik
.
## S3 method for class 'maxLik' nObs(x, ...)
x |
a statistical model estimated by Maximum Likelihood
using |
... |
further arguments (currently ignored). |
The nObs
method for objects of class "maxLik"
can return the number of observations only
if maxLik
was called
with argument grad
equal to a gradient function or
(if no gradient function is specified)
argument logLik
equal to a log-likelihood function
that return the gradients or log-likelihood values, respectively,
for each observation.
numeric, number of observations
Arne Henningsen, Ott Toomet
## fit a normal distribution by ML # generate a variable from normally distributed random numbers x <- rnorm( 100, 1, 2 ) # log likelihood function (for individual observations) llf <- function( param ) { return( dnorm( x, mean = param[ 1 ], sd = param[ 2 ], log = TRUE ) ) } ## ML method ml <- maxLik( llf, start = c( mu = 0, sigma = 1 ) ) # return number of onservations nObs( ml )