altered {VGAM} | R Documentation |
Return the altered, inflated, truncated and deflated values in a GAITD regression object, else test whether the model is altered, inflated, truncated or deflated.
altered(object, ...) inflated(object, ...) truncated(object, ...) is.altered(object, ...) is.deflated(object, ...) is.inflated(object, ...) is.truncated(object, ...)
object |
an object of class |
... |
any additional arguments, to future-proof this function. |
Yee and Ma (2021) propose GAITD regression where values
from four
(or seven since there are parametric and nonparametric forms)
disjoint sets are referred to as special.
These extractor functions return one set each;
they are the alter
, inflate
, truncate
,
deflate
(and sometimes max.support
)
arguments from the family function.
Returns one type of ‘special’ sets associated with GAITD regression.
This is a vector, else a list for truncation.
All three sets are returned by specialsvglm
.
Some of these functions are subject to change.
Only family functions beginning with "gaitd"
will
work with these functions, hence
zipoisson
fits will return FALSE
or empty
values.
Yee, T. W. and Ma, C. (2022). Generally–altered, –inflated, –truncated and –deflated regression, with application to heaped and seeped data. In preparation.
vglm
,
vglm-class
,
specialsvglm
,
gaitdpoisson
,
gaitdlog
,
gaitdzeta
,
Gaitdpois
.
abdata <- data.frame(y = 0:7, w = c(182, 41, 12, 2, 2, 0, 0, 1)) fit1 <- vglm(y ~ 1, gaitdpoisson(a.mix = 0), data = abdata, weight = w, subset = w > 0) specials(fit1) # All three sets altered(fit1) # Subject to change inflated(fit1) # Subject to change truncated(fit1) # Subject to change is.altered(fit1) is.inflated(fit1) is.truncated(fit1)