nobs
Extract the Number of Observations from a Fit
Description
Extract the Number of Observations from a Fit
Usage
nobs(object, ...)
## Default S3 method:
nobs(object, use.fallback = FALSE, ...)
## S3 method for class 'glm':
nobs(object, ...)
## S3 method for class 'lm':
nobs(object, ...)
## S3 method for class 'nls':
nobs(object, ...)
Arguments
| object |
object inheriting from fitted model or list with "nobs" components.
|
| use.fallback |
logical value, if TRUE,
use the length of the object's weights or residuals component
if they exist and there is no nobs component
|
| ... |
additional arguments for future functions.
|
Details
The default method returns the nobs component of object
if it exists.
If use.fallback is TRUE the default method will return the
length of the weights component (if it exists) or the
length of the residuals component (if it exists and weights
does not).
The "glm" method returns the length of object's
weights component.
The "lm" returns the length of object's weights component
excluding the zero-weights or the length of the residuals component
if there is no weights component.
The "logLik" method
returns the "nobs" attribute of object.
The "nls" method returns
the number of non-zero weights if there are weights in the model,
otherwise the number of rows in the data after rows with missing values
are removed and the desired subset is extracted.
Value
a numeric value that indicates the number of observations.
See Also
Examples
z1 <- list(x=c(1, 2, 3), nobs=3)
nobs(z1)
## [1] 3
z2 <- list(x=c(1, 2, 3), nobs=c(3, 4))
nobs(z2)
## [1] 3 4
z3 <- list(x=c(1, 2, 3), residuals=1:13)
nobs(z3, use.fallback=TRUE)
## [1] 13
g1 <- glm(ozone ~ radiation + poly(wind, temperature, degree = 2),
data = Sdatasets::air)
nobs(g1)
## [1] 111