# Add or Drop All Possible Single Terms to a logistf Model

### Description

Compute all the single terms in the scope argument that can be added to or dropped from the model, fit those models and compute a table of the changes in fit.

### Usage

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### Arguments

`object` |
a fitted logistf object |

`scope` |
The scope of variables considered for adding or dropping. Should be a vector of variable names. Can be left missing; the method will then use all variables in the object's data slot which are not identified as the response variable. |

`test` |
The type of test statistic. Currently, only the PLR test (penalized likelihood ratio test) is allowed for logistf fits. |

`...` |
further arguments passed to or from other methods. |

### Details

`drop1`

and `add1`

generate a table where for each variable the penalized likelihood ratio chi-squared, the degrees of freedom, and the p-value for dropping/adding this variable are given.

### Value

A matrix with `nvar`

rows and 3 columns (Chisquared, degrees of freedom, p-value).

### Author(s)

Georg Heinze

### Examples

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