R: Altered, Inflated and Truncated Values in GAIT Regression

altered {VGAM} | R Documentation

## Altered, Inflated and Truncated Values in GAIT Regression

### Description

Return the altered, inflated and truncated values in a GAIT regression from a fitted object

### Usage

    altered(object, ...)
    inflated(object, ...)
    truncated(object, ...)

### Arguments

`object` | an object of class `"vglm"`.
`...` | any additional arguments, to future-proof this function.

### Details

Yee and Ma (2020) propose GAIT regression where values from three disjoint sets are referred to as special. These extractor functions return one set each; they are the `alter`, `inflate`, `truncate` (and sometimes `max.support`) arguments from the family function.

### Value

Returns one type of ‘special’ sets assoicated with GAIT regression. This is a vector, else a list for truncation. All three sets are returned by `specialsvglm`.

### References

Yee, T. W. and Ma, C. (2020). Generally–altered, –inflated and –truncated regression, with application to heaped and seeped count data. In preparation.

### See Also

`vglm`, `vglm-class`, `specialsvglm`, `gaitpoisson.mix`, `gaitlog.mix`.

### Examples

    abdata <- data.frame(y = 0:7, w = c(182, 41, 12, 2, 2, 0, 0, 1))
    fit1 <- vglm(y ~ 1, gaitpoisson.mix(inflate = 1), abdata, weight = w,
                 subset = w > 0)
    altered(fit1)
    inflated(fit1)
    truncated(fit1)
    specials(fit1)  # All three sets

[Package VGAM version 1.1-3 Index]