family(object) binomial(link=logit) gaussian() Gamma(link=inverse) inverse.gaussian() poisson(link=log) quasi(link=identity, variance=constant)
link
|
a specification for the model link function.
The binomial family admits the links; logit ,
probit and cloglog (complementary log-log),
the Gamma family the links; identity ,
inverse and log ,
the poisson family the links; identity
log and sqrt , and
the quasi family the links; logit ,
probit , cloglog , identity , inverse ,
log , 1/mu^2 and sqrt .
The other families have only a single permissible
link function. These are the identity for the gaussian
family and 1/mu^2 for the inverse.gaussian family.
The function power can also be used to create a
power link function for the quasi family.
|
variance
|
for all families, other than quasi ,
the variance function is determined by the family.
The quasi family will accept the specifications
constant , mu(1-mu) , mu , mu^2 and
mu^3 as variance function.
|
object
|
the function family accesses the
family objects which are stored within objects
created by modelling functions (e.g. glm ).
|
glm
.
See the documentation for glm
for the details on
how such model fitting takes place.
Dobson, A. J. (1983). An Introduction to Statistical Modelling. London: Chapman and Hall.
Cox, D. R. and E. J. Snell (1981). Applied Statistics; Principles and Examples. London: Chapman and Hall.
glm
, power
.