offset
Set an Offset Value in a Modelling Formula

### Description

Allows you to specify an offset value to subtract from the response in a formula.

### Usage

    offset(object)

### Arguments

object | An expression.

### Details

This function is used only on the right side of a formula, to specify an expression to be subtracted from the response (on the left side of the formula). For glm models this subtraction is done after the inverse-link function is applied to the response.
Value
The same as the input.
See Also
formula, glm, lm, terms.
Examples

    # fit response to Start and Age
    fit1 <- glm(Kyphosis ~ Start + Age,
                data=Sdatasets::kyphosis, family=binomial)
    # fit response to Start, assume coefficient of Age is 0.01
    fit0 <- glm(Kyphosis ~ Start + offset(0.01 * Age),
                data=Sdatasets::kyphosis, family=binomial)
    # compare the fits: is estimates Age coefficient different than 0.01?
    anova(fit0, fit1)

Package stats version 6.1.5-18
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